Unlimited Fafnir:Volume 1 Chapter 3

Chapter 3 - "White" Leviathan

Part 1

I defied the destiny he had decided for me.
No matter what kind of battlefield I was sent to, I always accomplished the mission without killing anyone.
Perhaps it was like acting obstinately out of spite. Normal common sense and morals would easily crumble against the education I received. In order to protect my beliefs that must not be compromised, relying on logic and conscience was not enough.
I did not want to become the type of person he hoped for. I wanted to continue being Mitsuki's brother. Feelings of this sort supported my obstinacy.
However, no matter how much I struggled, I always felt a premonition that everything would end up in futility.
He did not reprimand me for my persistent resistance. As long as I produced satisfactory results, he even praised me.
Hence, I knew clearly that I was still under his control.
Even if I still managed to keep my hands untainted, from past to present, the day for my hands to be tainted would inevitably arrive.
So long as I continued to fight under NIFL, that destiny was impossible to change.
It was ultimately just a matter of time.
I was sent to battlefields that were countries where public order had broken down due to dragons passing through. Those kinds of places were mostly in civil war to begin with.
Using dragons as excuses, NIFL kept intervening in regional conflicts.
Brothers-in-arms fighting alongside me gradually increased, their numbers finally settled at eight.
They were young men brought from other places, each possessing their own outstanding talents.
Named Sleipnir, my team galloped on numerous battlefields.
According to him, there was apparently an intended enemy we were meant to fight. Putting down guerilla groups was just practice before the real battle. Nevertheless, we were still risking our lives all the time.
In a world where life and death were thinly divided, how much longer could I act obstinately out of spite?
Was defiance more important than my own life?
These thoughts always occupied my mind during fighting.
Also, I was probably still going to turn into a killer in emergency situations. Somewhere in my heart, the notion of giving up had already manifested.
Because I had already become a person who could actually kill provided I wanted to.
I had already been remade into that kind of person.
My trigger finger no longer trembled from my conscience's reprimands. Neither did it hesitate in pity for the target.
Before arriving at NIFL, I had already lost my sense of fear.
I possessed all the requirements to become a killer.
Ironically, the reason why I had the luxury of acting out of spite was because he had made me strong.
Purely because I was not strained, I had the luxury of choosing whether to kill or not, hence I chose not to kill.
Once that slack was lost, my resistance was probably going to end.
That was what I originally thought, but—
"I won't lose!"
The day I was liberated from NIFL, I met the strongest human out of all the opponents I had faced so far—a D—and fought her.
She was actually not that dangerous a person, but from my perspective in ignorance, she was a monster with firepower surpassing tanks.
To eliminate the lethal threat, my body moved on its own. Faster than my thoughts, subconscious intent to kill had already sprung into action in advance.
But that was not my first time encountering a life threatening crisis. Even when faced with a gun in front of my face, I had always handled situations calmly in composure.
The reason why I lost that composure so easily that time... was most likely because she was a D.
Encountering the intended enemy, the monster growing inside me bared its fangs on its own.
But I used my willpower to stop the swing of my arm.
I defied the reason of my own existence.
I chose not to kill her.
I made that choice successfully.
Hence, I owed her a debt impossible to repay.
Because she—Iris—proved that my spite-fueled obstinacy was more important than my own life.

Part 2

The day the test ended, dinner was a bit different from usual.
"This is—?"
After the dishes were cleared off the table and I saw the food brought by the housework robot, I asked Mitsuki who was sitting opposite me across the table.
"Is it not obvious? This is dessert!"
"Dessert? Why just today..."
Baked pudding topped with cream. Bits of chocolate were even sprinkled beautifully over it. Looking at this dessert, I inquired of her.
"Although you only qualified as backup, this is to reward you for passing, Nii-san, because I believe that hard work should be commended."
Without looking at me, Mitsuki answered in an indifferent tone of voice.
"Uh, it looks really tasty. Thank you very much... Did you actually make this for me, Mitsuki?"
"W-What, what makes you think that?"
The fork fell from Mitsuki's hand. Unable to hide her shaken heart, she asked me.
"Lisa mentioned it. She said you make lovely sweets, so I wondered whether this was your creation too."
"U-Umm..."
"Judging from your reaction, I guess I'm right?"
"...Yes."
Mitsuki huddled herself and admitted in a small voice.
"Then why not say that from the start? I am very grateful to you."
"Because... It would be very embarrassing if it failed to suit your tastes, Nii-san. Also, I would not hear an honest opinion."
Mitsuki looked away and said with her face red.
"Sheesh... I thought you'd grown braver after becoming the student council president, but you're still so timid on weird issues."
Laughing wryly, I scooped a spoonful of the dessert and tasted it. The gentle and sweet flavor immediately started spreading from the tip of my tongue.
"—Mmm, super good."
"R-Really?"
"Yeah, and the entire schools students have already recognized your skills, right? I think you could be more confident."
"If the person before me says it does not taste good, the opinion of the majority will be completely meaningless."
Mitsuki asserted with a serious expression.
"...I think I'm starting to understand why you're able to become the student council president."
Exhaling in exclamation, I finished all of the dessert.
"—Thanks for the treat. Dessert was lovely. Thank you, Mitsuki."
"Great, you are welcome."
At this moment, the expression on Mitsuki's face reminded of three years ago—that extremely natural and incomparably relaxed smile.


After the meal, I returned to my room to find the lamp on my portable terminal flashing.
Looking at it, I found an email from Iris. This portable terminal was capable of voice calls and email, but the only contacts I had so far were limited to Mituski and Iris.
'I'm waiting for you at the beach.'
That was all she wrote.
I looked at the time displayed on the edge of the portable terminal's screen.
"7:27pm huh... Curfew starts at 8pm so I guess it's fine."
Taking the portable terminal, I left the room, walking while writing an email to Mitsuki.
'I'm going out for a bit. Back by 8pm.'
Because Mitsuki would probably check the dorm's entry and exit records, I thought I had better inform her.
I left the dorm and walked on the road along the shore.
Without any basis at all, I felt that she was probably waiting for me at the place where we first met. Because time was limited, I quickened my pace to hurry on my way.
Countless stars were twinkling in the deep-blue night sky. Waves kept surging and retreating, as though caressing the white beach, playing a regular song of the sea.
My intuition was apparently correct. Iris was standing at the place where our eyes first met. Although she was in uniform, she had taken off her shoes and stockings to go barefoot.
With the waves breaking over the snow-white complexion of those beautiful feet, Iris was staring at the sea surface afar.
I walked over the sand to approach her, resulting in rustling footsteps. Hearing my footsteps, Iris turned her head in my direction.
"Oh... Mononobe, you came."
"Yeah, because your email said you're waiting for me."
I stopped several meters in front of Iris and replied.
"Sorry for calling you out at this hour. Did Mitsuki-chan get angry?"
"I'm supposed to be able to go out before 8pm... But she might be angry when I get back."
"Fufu, because Mitsuki-chan is very strict!"
Seeing Iris' smile, I felt my heart pounding. Bathed under starlight, the silver-haired girl was giving off an even more otherworldly sense of beauty than usual.
"...Then why did you want to see me?"
I asked her while being aware of the nervousness in my voice.
"Oh, umm, first is, umm... I want to thank you, Mononobe."
"If it's thanks, you already thanked me countless times after the test. It's more than enough. Besides, I didn't do anything that needs you to thank me like that."
"You're wrong! If it weren't for you, Mononobe, I definitely would have failed again, so—Thank you!"
Iris bowed her head forcefully to thank me, her long silver hair spreading out in the air.
"I simply trained together with you... Fine, you're welcome."
Further refusal would just be a waste of time, so I candidly accepted her thanks.
"U-Umm, then... I've got something to ask you, Mononobe... Can I?"
Iris looked up stiffly and asked in trepidation.
"I don't mind..."
I nodded and Iris approached me.
"Mononobe, why did you help me?"
"Huh?"
"Being so considerate of me, working hard with me seriously, Mononobe, you're the first person to do that. Everyone else in the class hold themselves and others to strict standards, so I can't rely on them... Although Mitsuki-chan looks after me frequently, I think that's because she's the student council president."
Iris approached me even closer, almost to the point of touching me.
"So, I wanna know... how you feel, Mononobe."
Seeing her gaze at me from so close, I felt my heart beat even faster.
"T-That's because..."
"Because...?"
"Probably because... you're very similar to how Mitsuki was in the past."
I said one of the reasons.
The debt I felt on my own was just my personal feelings after all. If I had to explain it to her, that meant bringing up things from my NIFL days, so I was not going to say much on that front.
"I'm similar to Mitsuki-chan? No way, I'm completely unlike Mitsuki-chan!"
"She used to have similarities with you, Iris, and right now, she is still working as hard as she can, just like you, so... I think that's why I can't leave you to your own devices."
Hearing my answer, Iris looked down and murmured quietly.
"I see... So that's the case, it's a bit unfortunate. But... it's fine, I just have to start trying hard now."
"Iris?"
I called to her because I could not hear her clearly. Iris instantly looked up forcefully.
"Mononobe!"
"W-What?"
"Listen here, I... want to get closer to you, Mononobe, s-so umm... If you don't mind, I want to be frie—"
WOOOOOOOOOOOOO...
Just as Iris was speaking, a loud siren was suddenly heard all around.
'Emergency warning, emergency warning—Level C alert, Type White. I repeat, Level C alert, Type White!'
The announcement explained the key points of the warning.
"Type White—that's 'White' Leviathan, right...? Is a Level C alert very urgent?"
I asked but Iris did not seem like she heard me.
"Leviathan..."
She said the dragon's name with a stiff expression.
Right—Iris had lost her family due to a dragon disaster caused by Leviathan.
'The Dragon Subjugation Squad, students selected by the Midgard Defense Department, please man your stations. Prepare to standby for combat operations. All other students and staff, please return to your quarters or the nearest evacuation shelter, especially those currently at shore areas, please evacuate as quickly as possible.'
"Hey, the announcer is telling us to evacuate!"
"...That dragon... is nearby..."
"Pull yourself together! Anyway, we need to get out of here first!"
Iris was in a trance. I grabbed her hand and pulled up up to the breakwater.
A deep noise and vibrations could be felt underfoot.
Looking out at sea, giant rectangular objects surfaced one after another from the originally peaceful sea. Then these objects formed a circle as though surrounding this island.
The displaced seawater formed big waves, rushing up the beach. Smashing against the breakwater, the waves broke into white spray.
"Could that be... Midgardsormr?"
"That's right. What's visible from here is just part of the final defensive line... The first to third defensive lines are farther out at sea."
Probably returning to her senses finally, Iris answered me calmly.
"Iris, you're okay now?"
"Yeah, I'm okay. Sorry for spacing out... We have to hurry and find shelter or else we'll cause other people trouble."
After speaking with a serious face, Iris put on the shoes she had placed on the breakwater before hand, then looked up into the night sky.
Uniformed girls holding weapons were passing overhead, flying towards the sea.
This was probably the Dragon Subjugation Squad selected by Midgard Defense Department. By generating wind, they were flying in the sky at high speed.
"That's true, we'll only get in their way if we stay here."
"Right, let's head back to the dorms immediately—Ooh..."
Iris was just about to break into a run when she suddenly knelt down with her hand on her stomach.
"Hey... What happened to you!?"
"A-A sudden stomach ache... Ahaha, maybe I ate too much to celebrate passing the test... Oh... It's gradually getting better..."
Despite the cold sweat already appearing on her forehead, Iris still stood up.
"...Can you walk?"
"No problem... Let's run, Mononobe!"
It seemed to be a momentary stomach ache. Iris took my hand and began to walk briskly.


Iris had to make her way to the shared dormitories located near the school so we separated along the way and I returned to Mitsuki's personal dorm.
"Mitsuki, are you here?"
I called out from the entrance hall, but no one answered. Mitsuki was apparently the Dragon Subjugation Squad's captain, so she had probably mobilized already.
Although I was curious about the situation outside, I could not ask her through email because it would obstruct her work. Hence, I decided to wait quietly and returned to my room.
Unable to settle down, I started wanting to find a book to read. The instant I touched the portable terminal, a ringtone was suddenly heard.
I initially thought it was Mitsuki, but the screen did not display the caller's number. No matter how long I waited, the ringing showed no signs of stopping, so I hesitantly pressed the button to take the call.
Immediately, an image with static appeared on the screen to show a young man in military uniform, grinning.
That smile made me feel a chill from the bottom of my heart.
'Hi, it's been a while, 2nd Lieutenant Mononobe.'
"Major Loki... Why—"
I uttered his name in a hoarse voice.
Major Loki Jotunheim—The person who used to be my direct superior until recently.
This man, who could be considered the mastermind behind NIFL, why—
'Well, I wanted to call you earlier... But Midgardsormr's defensive line includes many barriers on electronic communications too. If it weren't for the current battle situation, communicating without Midgard's knowledge would be impossible. Sorry for calling late.'
"Calling late... I wasn't waiting for a call from a guy like you—"
'A guy? In just a brief week, 2nd Lieutenant Mononobe, have you forgotten how to address your former commanding officer?'
Narrow eyes stared straight at me from the screen. Just by doing that, he made me feel like I was pulled back to the past, pulled back to those long, dark days when I was working under him.
"...My apologies, Major Loki."
'Now that's more like it. Still, I can hardly blame you for growing lax. Compared to NIFL, Midgard is like paradise. It's only inevitable that you would be affected, given your incompleteness. Seriously... It is truly unfortunate that I couldn't finish you up in the end."

"You called me... Why?"
'Oh right, I almost went on a tangent. It's like this, I have a favor to ask of you.'
"A favor?"
'Our positions no longer allow me to command you, so this is a favor. 2nd Lieutenant Mononobe, you already know that Ds can turn into dragons, right? This is top secret at NIFL but it should be something that all Midgard students are privy to.'
Smiling artificially, Major Loki asked me.
"...Yes, if a D makes contact with a dragon after her dragon mark changes color, she will turn into the same type of dragon. Are you referring to this phenomenon?"
'Indeed, how terrifying. To think that such monsters could multiply, a most frightful notion chilling to the bone. An outcome that must be prevented at all costs, do you not agree?'
"Y-Yes... Of course."
Despite a foreboding feeling, I still concurred.
'But despite its crucial position, Midgard has not perfected its handling of this matter. After confirming that a dragon mark had changed in color, they send the subject to an underground bunker for isolation, then have other Ds intercept the dragon. This is the tactic they have chosen.'
"That kind of tactic... What's wrong with it?"
'Are you playing dumb? It should be quite clear to you. The most effective countermeasure is to kill the D whose dragon mark has changed in color.'
The chill given off from Major Loki's inexorably cold eyes almost seemed to freeze my heart.
"...No one can support that, whether on grounds of human rights or the social value of Ds. One D's death is a massive loss to the world."
Besides, who would be capable of making that kind of proposal?
Despite the threat of dragons, the world continued to develop slowly, maintaining some measure of peace. It was all thanks to these Ds bolstering energy resources.
'But I believe that the economic and human losses arising from an increase in dragons would dwarf the benefits. But just as you say, it is true that such a method won't be supported by the majority. Because the world fears offending the Ds while the Ds won't abandon one of their own. After all, any one of them could be the next victim.'
"Then—"
'Hence, someone needs to act in secret.'
Major Loki interrupted me, his eyes fixed upon me.
"You're not ordering me, by any chance?"
'Not an order. I am simply asking you to accept the mission as a favor to me. Your reassignment to Midgard was completely unexpected, but I already had prior plans to have someone infiltrate. If you could take on this mission, it saves a lot of work. Don't worry, all you need to do is kill one D if an emergency arises.'
"Please don't... make it sound so easy."
I gritted my teeth and glared at Major Loki.
'It is very easy, at least to the 2nd Lieutenant Mononobe I cultivated. Whether Ds or anyone else, as long as the opponent is human, you won't lose, because you are the strongest Fafnir from our Sleipnir."
"..."
I could not say anything. Major Loki's words were just a curse, not praise.
'You don't have to answer immediately. But if your assistance cannot be secured, I might have to resort to less efficient means, which might cause unnecessary collateral damage. So please consider the matter carefully.'
Zzzt. The call disconnected and the screen went black.
Leaning myself against the back of the chair, I looked up at the ceiling.
The siren still continued to blare.

Part 3

The alert of an approaching dragon was finally lifted about three hours later.
But late night arrived and Mitsuki still did not return. The next time I saw her was already the full-school assembly the next morning.
"I believe that everyone should know already that at 7:41pm last night, there was a Level C alert situation. The approaching dragon is 'White' Leviathan that circles the Pacific Ocean along a fixed route. But this time, it has deviated from that route to trespass Midgard's warning zone."
Standing on the podium, Mitsuki explained the situation. This was probably part of the student council president's job.
"Leviathan stayed roughly three hours in the warning zone but returned to its original route without reaching the first defensive line. These irregular exceptions seem to occur once in a while. A year ago, a passenger ship was sunk due to this reason."
A year ago... Ship... Would that be the dragon disaster that Iris had been caught up in?
Looking at silver hair, I wondered to myself. Since students were lined up according to their Student No., Iris was in front of me.
Iris did not react to what Mitsuki had just said. With her hand on her stomach, perhaps that stomach ache from yesterday was still persisting.
"If Leviathan attacks, it will be quite an arduous battle. Leviathan is considered second only to 'Yellow' Hraesvelgr in how troublesome they are to handle. Wielding the power of universal repulsion known as antigravity, Leviathan presents a great challenge, be it approaching or attacking its body. However—"
Mitsuki leaned forward and slowly swept her gaze over all the students of the school.
"Even if one of you were to attract Leviathan, causing it to attack, the Dragon Subjugation Squad will still fight fearlessly. We will not abandon you no matter what. Consequently, if any of you feel that your dragon mark has changed, please do not hesitate. Step forward and let us know. I will put my life on the line to protect you."
Mitsuki declared clearly. Strong conviction could be felt from her words. It was not simply a sense of obligation.
Thunderous applause started up.
However, Iris did not clap even though she had felt moved by Mitsuki's previous speech. Her slender shoulders were shivering while she had her head lowered.


"Eh, where's Iris?"
After the assembly, I returned to the classroom to find Iris missing.
"Who knows? She was apparently feeling unwell, so she probably went to the infirmary, right?"
Lisa's gaze met mine while she answered with displeasure.
"Oh, you also noticed Iris didn't look her usual self, Lisa?"
"Of course. Rather, you seem quite concerned about about Iris-san. You wouldn't be harboring ulterior motives, would you?"
Lisa gazed at me with eyes of suspicion.
"Just like you, Lisa, I'm simply worried about her."
"What... I-I am not—"
At a loss for words, Lisa looked away.
Just at this moment, Mitsuki entered the classroom. I decided to ask her about Iris' whereabouts.
"Iris is missing. Did you hear anything, Mitsuki?"
"No, I have not..."
If Iris had gone to the infirmary, she should have asked me or Mitsuki to tell the teacher. My heart began to grow inexplicably uneasy.
"I'll go look for her. Tell the teacher for me, okay?"
"Hey wait, Nii-san!"
Leaving behind Mitsuki who called me frantically, I entered the corridor. Next period was about to begin and there were almost no students out in the hallways.
I made my way quickly to the infirmary first. I knew where to go because I brought Iris there last time when she fainted from the explosion. Reaching the adjacent building, I went to the corner of the first floor and opened the door marked "Infirmary," but Iris was not there.
"Sheesh... Where did she go?"
Did her stomach ache hurt so much that she could not move? I tried searching along the path to the gym but still could not find her.
"Maybe... in a washroom?"
If she was in a washroom, there was nothing I could do. It was also possible that my worries were unnecessary. I decided to return to the classroom first so I turned back from the gym.
There was a corridor linking the gym and the school building. From there I could see tropical flowers blooming in the courtyard. Just as I shifted my gaze upwards, I suddenly discovered a figure on the school building's roof.
"What...?"
A strong breeze was blowing beautiful silver hair. The girl was quietly staring at the ground below.
Seeing her like that, I instantly felt the surge of an ominous feeling. Immediately, I sprinted.
Dashing into the school building, I rushed up the stairs and smashed myself against the door to reach the roof.
The loud crash caused the silver-haired girl, leaning against the roof railing, to look back.
"Mononobe?"
"Sure enough, it's you, Iris..."
Iris's eyes were wide open. Looking at her, I sighed. When I saw her just now, for just an instant, I thought she was going to jump, but I suppose I was worrying too much.
"Why did you come here?"
"I want to ask you the same question. It's almost class time, you know?"
"I... will skip next period."
Iris smiled wryly and sat down on the concrete. Her hand was still pressed against her stomach.
"What exactly is the matter?"
"I need time to calm down."
On closer examination, what Iris was holding was her flank. I recalled her nude body and its snow-white complexion that I saw by chance the first time we met. Speaking of which, her dragon mark happened to be near that spot—
"...Iris, do you have a stomach ache?"
"..."
"If you don't mind, could you show me where you're hurting?"
"Mononobe, you're so perverted."
Iris huddled her body and glared at me.
"Oh, no, you misunderstand me."
I was trying to find an excuse when Iris chuckled then exhaled gravely.
"—I know. Sorry for saying something malicious like this."
Iris pulled up her uniform to expose her abdomen.
My heart instantly raced like mad. My gaze getting drawn to Iris' skin was admittedly one of the reasons, but the bigger reason was surprise. The dragon mark branded on Iris' flank was shining with faint silver-white light.
"That... Starting when—"
"I only discovered it this morning, but I think it already started changing last night."
Iris spoke in monotone.
"You still haven't told anyone?"
"...I haven't."
Iris nodded with a gloomy expression.
"Why? Mitsuki said she absolutely won't abandon anyone. She'll put her life on the line to protect you!"
"That's why I didn't confess. 'White' Leviathan is one of the dragons for which there are no effective countermeasures, but if for my sake... if everyone has to fight for the sake of protecting someone like me, is it really okay...?"
Iris gazed out into the distance on the other side of the railing.
"No way—Are you planning to jump off the building to commit suicide before the situation reaches that point?"
I grabbed Iris' shoulder and pulled her back, because I feared what she might do if I did not hold her tightly.
But Iris smiled wryly and shook her head.
"I thought of that too... But I'm too scared, can't do it. I'm not a girl with that kind of mental strength."
"...Thank goodness you're a coward, Iris."
"Jeez, what do you mean by that!?"
Iris pouted.
"Even if you kill yourself now, it's possible that another D might get targeted soon enough. That wouldn't accomplish anything except postponing the problem. Unless the dragon is defeated, it doesn't solve the problem at the root."
—The most effective countermeasure is to kill the D whose dragon mark has changed in color.
Major Loki's words flashed through my mind.
It definitely could resolve a crisis momentarily. In terms of preventing the worst-case scenario, this might be the safest method. However, if this were to be repeated, all the Ds would go extinct eventually.
"Yeah... I know that too but even so, I'm still afraid."
"You don't believe in Mitsuki and the others?"
"That's not it... I'm afraid of the fact that I won't be able to kill myself. Once the final defensive line is breached, when we really are out of options... Unable to commit suicide, I'll surely become a dragon. In that event, I'll harm everyone! I don't want that... Anything but that..."
Irisi hugged me, speaking words from the heart. Precisely because she felt such a strong sense of duty towards fighting dragons, she was this scared of becoming a dragon disaster herself.
—Someone needs to act in secret.
Major Loki's voice sounded deep in my ear again.
No matter what, the world could not run normally unless someone did the dirty work. It felt very paradoxical, but it was the truth.
The people of Midgard were not stupid. Despite what she said, Mitsuki had probably prepared a last resort to use for emergencies.
If that was the case, there should not a problem with me taking on that job. At the same time, I could also restrain Major Loki, to prevent him from unnecessarily interfering.
"Don't worry, Iris, you absolutely won't turn into a dragon."
I committed my determination and hugged Iris tightly.
"Eh...?"
Indeed, now was the time to return my debt.
Iris had proven my obstinacy, telling me that even if I had to weigh my own life against it, I was still capable of choosing not to kill.
That time, because I was facing Iris, that was probably why I managed to regain self-control.
Because I was attracted to her beauty in the instant of our encounter, that was why I could regard her as just a girl instead of a D.
It made me feel that I would rather die than kill her.
Hence—
"If the situation worsens so much that we're out of options, I will do it—I will kill you, Iris."
I made my choice by my own will again.
If it was for Iris' sake, I will kill Iris.
I will put the obstinacy, which I had adhered to for the past three years, on the line.
To this date, I had avoid tainting my hands, but it was only for the sake of guarding my heart.
Iris' wish of not wanting to harm others was far more noble than mine.
And I wanted to help her achieve her wish.
"Mononobe, you...?"
"Yes, so you can relax and let Mitsuki's team protect you for now. Until the final moment arrives, I absolutely won't give up either."
I gently stroked her soft, silver hair and replied. Iris looked up with moistened eyes at me.
"Can I... believe you?"
"Leave it to me. Although I've kept quiet about it so far, I'm actually the world's strongest assassin—The candidate for that."
Hearing me say that, Iris was stunned for a moment before her lips curled lightly to smile.
"Fufu—You must be kidding!"


After that, I accompanied Iris back to the classroom and explained the situation to Mitsuki.
Then Mitsuki immediately declared a Level A alert state of emergency.

Part 4

On this liberating island in the south with beautiful weather, the atmosphere and scenery changed dramatically. The windows in buildings had shutters lowered to defend against shockwaves. Normally kept underground, anti-air weapon stations popped out all over the island.
The concentric defense system of Midgardsormr had entered interception mode completely. Its intimidating formation had the entire horizon covered.
In contrast, the school disappeared. The school building and the clock tower, where the most important facilities were located, were all hidden underground, sealed inside partitions made of mithril.
Entering school premises required passing through underground passages connected to the various dormitories and emergency. It was only today that I finally learned that Mitsuki's personal dorm also had an entrance to an underground passage.
"So late..."
I was sitting on the stairwell at the entrance hall, staring at the ajar door in the wall beside me, leading to the underground passage.
It was currently 2am. I would normally be asleep so my eyelids felt very heavy.
I could hear faint sounds of airplanes outside. These were probably reconnaissance planes patrolling in Midgard's surroundings.
While I was half asleep, the door leading underground opened on its own with an electronic sound.
"Welcome back, Mitsuki."
I called to my sister whose face showed exhaustion.
"...!? N-Nii-san? Please do not startle me. Have you not gone to bed?"
Staring at me, Mistuki seemed seriously surprised.
"I was waiting for you, Mitsuki. Are preparations complete to intercept Leviathan?"
After I asked, Mitsuki replied with seriousness returned to her face:
"Although it is not perfect by any stretch... Leviathan has entered its route circling the Pacific Ocean. It is expected to approach again thirty-three hours from now. Before that, we should be able to reach full readiness."
Thirty-three hours later...
I repeated it silently in mind in order to commit this information to memory. Then I asked another question:
"So... How's Iris?"
"She had been receiving body checkups and diagnoses until just now. After all, she is the first person to have her dragon mark change color in the past two years, so there is a dearth of information. Being targeted by a dragon is very terrifying, but Iris-san has been cooperating with us without panicking at all."
It was most likely because Iris had already resolved herself. If that was the case, I had better keep my promise.
"Mitsuki, what should I do?"
"Nii-san... because you only passed as a reserve member in the Basilisk drill, you will not be summoned for the Dragon Subjugation Squad. Presumably, you will be asked to stay on standby in shelter like ordinary students."
Nothing to do, in other words? In that case, perfect.
"If that's the case... Can you assign a job for me, who has nothing to do?"
"A job?"
"Yes, as Iris' bodyguard."
I made this demand which I would have found it impossible to bring up in the classroom with everyone present.
Mitsuki frowned in surprise.
"The Dragon Subjugation Squad is fighting to protect Iris-san. Your participation is not needed, Nii-san."
"That's against dragons as opponents, right? By bodyguard, I mean protecting Iris from threats other than dragons."
Hearing what I said, Mitsuki's expression instantly froze. She seemed to understand immediately.
"You are saying... that someone might target Iris-san's life?"
"At least NIFL doesn't trust Midgard. They might interfere unnecessarily."
Mituski narrowed her eyes after hearing what I said.
"Judging from your tone, Nii-san, you seem to have some kind of concrete evidence?"
"Yesterday, my commanding officer at NIFL, Major Loki, contacted me."
"What..."
Mitsuki gasped in surprise.
"The Major has apparently made up his mind to prevent an increase in dragons. Just by assigning me as Iris' bodyguard, NIFL will be reassured to some extent."
"In other words, at a critical moment, Nii-san, they will have you kill Iris-san?"
Mitsuki stared at me with eyes of determination.
"Yes, but that critical moment will be decided by me. Until then, I will not allow anyone to kill Iris, no one at all."
I took on Mitsuki's gaze directly and answered her that way.
"...Your description makes yourself sound like the grim reaper, Nii-san."
"Yeah... But in a certain sense, that's precisely my original job. Mitsuki, you're probably aware given your position, right? Although I was never deployed in an actual operation of that sort... The reason why Sleipnir, the team I used to be part of, was established, its real purpose was to target Ds who've been deemed as disasters, to assass—"
"Enough!"
Mitsuki cried out loudly to interrupt me.
"...Please say no more. I wish to hear none of that from your own mouth especially. Nii-san, please remain the Nii-san I know."
With tears glimmering in her eyes, Mitsuki pleaded to me.
"Mitsuki..."
"Regarding the bodyguard matter... I permit your request, because it seems to be the only way right now to keep NIFL restrained, but I have one condition."
"Condition?"
Seeing Mitsuki's gloomy eyes, I asked uneasily.
"If the situation reaches the point when Iris-san's dragonification is truly unavoidable—I shall do it then."
"What... No way! I can't let you do that kind of thing, Mitsuki!"
I yelled frantically but Mitsuki smiled wearily and shook her head.
"—It is fine, because my hands are already tainted."
"What do you mean by that?"
"Two years ago, the one who killed the fellow D who had turned into a dragon... That was me."
After saying that, Mitsuki walked past me and swiftly went up the stairs.
By the time I regained my senses from the shock and looked back, Mitsuki was already out of sight—


'—Really, you will accept this mission? That's really great help for me. And to think you've already secured the job as bodyguard to the target, you really work fast. I'm so fortunate to have such an outstanding subordinate like you. Ahhh, but you're not my subordinate anymore.'
Hahaha, Major Loki laughed superficially. Ignoring him, I continued.
"Anyway, because of that, please don't interfere anymore. I will definitely accomplish the mission."
'Very well, I understand. I will not do anything to obstruct you. Well then—I trust you, 2nd Lieutenant Mononobe.'
Zzzzt, the call disconnected.
"There is no one least suited to speaking the word 'trust' than you."
Muttering sardonically to myself, I laid myself on the bed.
After the conversation with Mitsuki ended, i returned to my room to get ready for bed, but as though aiming for this opportunity, Major Loki called at this time.
Because I already decided there was a need to contact him again, this timing turned out just right, except it felt a little terrifying.
"I can't lower my guard..."
Looking up at the ceiling, I spoke.
Mitsuki's words were also occupying my mind the whole time.
Just like I had gone through great changes over the past three years, Mitsuki must have experienced a lot.
Although no matter what things had happened, no matter what sins she was shouldering, I had no intention of handing Iris over to Mitsuki.
I had said to Iris: Leave it to me.
And three years ago, I had also said to Mitsuki: Leave everything to me.
I will not break... that promise.

Part 5

The next day, I went to school through the underground passage from the dormitory.
That being said, given the current emergency, lessons were naturally suspended at school. Walking through quiet and deserted hallways, I took the elevator and pressed the button at the bottom.
After experiencing the long descent, I finally reached the shelter that was located even deeper than training site number three. In front of a door in the corridor ahead, I could see a blonde girl standing there.
"It seems it's true that you will be in charge of monitoring Iris-san."
The girl—Lisa—looked at me with disdain.
"I'm not monitoring her, just a bodyguard. Have you accompanied Iris all this time since yesterday?"
My question prompted Lisa to puff out her chest and nod.
"Because we are classmates. When a classmate is in need, extending a helping hand is only natural."
"I see, you are considerate for your friends after all, Lisa."
"W-What do you mean by after all!? What do you know about me anyway!?"
Lisa glared at me with her face red.
"We've spoken so many times, it's only natural I'll gain a certain level of understanding. Right now, you're staying by her side because you're worried about Iris, right?"
"...For people like us who are living outside, separated from parents, classmates are equivalent to family. How could I not worry about her?"
Lisa shifted her gaze away, murmuring her answer quietly.
"Since you care about her so much, why not treat her more gently day to day...? Iris is always hard on herself for being called a poorly performing student."
Lisa whimpered "ooh..." then shook her head forcefully as though pulling herself together before glaring at me again.
"T-Those known as older sisters often act strict towards their younger sisters! Only family members can speak their minds without reservation, right?"
Her allegation made me think inside.
Indeed, gentle treatment was not the only expression of love and care. Iris was probably able to work so hard because someone existed to point out her flaws mercilessly.
"...I guess. Perhaps it's better if you continue with what you're doing, Lisa. Now that I think about it, you're quite an excellent older sister."
"Y-You will not gain anything from flattering me!"
Perhaps out of embarrassment, Lisa was speaking in a shrill voice.
"I'm not looking to gain anything either."
I shook my head wryly.
"That better be the case. Oh, just for the record, I still have not acknowledge you as a member of the class, so familial affection does not apply to you. Please do not forget that."
"—Got it. Anyway, I'll take your place from now on. You haven't slept since yesterday, right? It's best that you rest in preparation for battle."
Hearing me, Lisa made a displeased look.
"I will do that without needing you to tell me. Frankly speaking, although you do not reassure me, you do get along with her the best. I suppose Iris-san will have an easier time staying calm with you by her side."
After saying that, Lisa left towards the elevator.
But I suddenly remembered something and called to her.
"—Lisa, do you know about the Kraken battle two years ago?"
"Of course I do. I was fighting on the frontlines then."
Lisa stopped before the elevator and answered without looking back.
"The one who defeated Kraken was... Mitsuki, right?"
"Yes, indeed. Mitsuki-san shot and killed two Krakens. Through her accomplishments from that time, she rose to her current position."
I felt that Lisa's tone of voice had become stiff.
"It sounds like you don't approve?"
"—I approved because there was no other choice back then. But emotions are a separate matter. I cannot forgive Mitsuki-san who has murdered family."
"Family...?"
"Oh dear, so your knowledge is limited. Two years ago, the one who was turned into a dragon was Student No. 4 of Brynhildr Class, Shinomiya Miyako. She was Shinomiya-sensei's younger sister."
Lisa spoke in a calm tone of voice, then entered the elevator. Without looking back, she said:
"Then I shall leave Iris-san in your hands."
The elevator doors then shut. Just as I was stunned on the spot, I heard a door open. The door behind me had opened.
"Mononobe..."
Seeing Iris dressed in a flimsy nightgown, I instantly felt my heart rate rise.
"I-Iris, you heard everything?"
"Yeah... I was waiting to thank Lisa-san, because she treated me so nicely yesterday, but I couldn't find a chance to interrupt—"
Scratching her head, Iris smiled wryly.
"You already knew about what we mentioned just now?"
"I've only heard others talk about it, because I only came to Midgard a year ago... By then, Mitsuki-chan was already the student council president."
"I see now... But let's put that aside. If you just got out of bed, get changed first. Otherwise, I won't know where to look."
The fabric of Iris' nightgown was very sheer and offered faint glimpses of her body's curves.
"...It's a bit embarrassing, but I'm okay with it if it's you, Mononobe. Don't mind it. Come in."
"You're asking me not to mind—Hey, hold on!?"
Iris grabbed my arm and pulled me into the room. The interior was bigger than I imagined. Because it was a shelter, I originally thought it would be more plain, but it felt no different from the dormitory rooms.
Inside the room was a very comfortable looking bed, a desk with a breakfast tray on it, and a large closet. There was also a door that seemed to lead to the toilet and bathroom.
There were no windows after all, but instead, there was a large monitor installed on the wall. The screen was divided into multiple screens, displaying the situation around Midgard.
"Come, Mononobe, sit down here."
Iris plopped herself on the bed and patted the spot next to her.
"...Sit there?"
"Yes."
Iris nodded with a serious expression, so I nervously sat down beside her.
Then Iris leaned herself against me and hugged my arm.
I could feel my arm surrounded by a soft sensation.
"H-Hey?"
"—Let me stay like this for a while. There will be more tests starting noon again, so let me lean against you until then..."
Hearing the words Iris squeezed out desperately, I exhaled. Although Mitsuki had mentioned earlier that Iris had cooperated calmly, she would still feel afraid and uneasy, right?
If doing this could give her a bit of strength, then I'll let her lean like this for now without making a fuss.
To prevent my imagination from getting carried away, I turned my attention to the island scenery shown on the screens.
One view seemed to be taken by a satellite from above. It showed Midgardsormr surrounding the island in four layers. Many ships could be seen outside of the first defensive line. Those were probably NIFL's battleships and carriers.
Other images showed the girls of the Dragon Subjugation Squad, patrolling the island's airspace. Firill, Ren and Ariella could be seen among them.
"Oh!"
Seeing something inappropriate, I could not help but cry out.
"You saw... Firill's panties, didn't you?"
Perhaps following my gaze to see the same view, Iris remarked quietly.
"N-No, but it's an image shown on screen, so it can't be helped. Rather, it's weird to be flying in the air while wearing a skirt, right?"
"Sure enough, guys are happy to see panties, right?"
Iris looked up at me and asked.
"What...? No way... how could that be possible!?"
"Ah, you looked away! Sure enough, you enjoy it, right?"
Iris leaned against me even more, forcing her gaze to meet mine.
"Doesn't the way you put it make me out to be a pervert!? Rather than enjoy, it's just a feeling of slightly profiting."
"Meaning that... You enjoy it a lot?"
"Urgh..."
Under her cold gaze, I could not speak for a while.
Staring at me like that for a while, Iris then asked in a barely audible voice:
"...Mononobe, will you be happy to see my panties too?"
"W-What are you saying so suddenly—"
Ignoring my panic, Iris continued with a blush:
"If you like it, Mononobe, I could show you? Because I've always wanted to... thank you."
Saying that, Iris lifted the hem of her nightgown.
My gaze was uncontrollably drawn to her.
Eh? Hey, hold on—
I gasped. My heart raced. I subconsciously gulped.
The hem was gradually lifted. I could not tear my eyes off that gradually exposed snow-white skin.
Iris' fingers trembled lightly. With her face bright red, she pulled the nightgown's hem even higher.
Her thighs, looking so soft and seductive, kept shaking my rationality. Finally, her nightgown was lifted up to near the base of the thigh.
Any further lifting and I would really see—
"Y-You don't need to thank me like that!"
Coming to my senses at the last second, I held Iris' hand down.
"Mononobe... You don't want to see mine?"
Iris was asking with a displeased look.
"It's not a matter of whether I want to see or not. What I mean is you shouldn't do something like that so lightly. Man are far dangerous creatures than you can imagine, Iris."
"...I am not doing this lightly. I had to gather a lot of courage to speak my mind."
"That's even worse. You have to treasure yourself more."
Perhaps Iris simply wanted to show me, but that would awaken even stronger desire. If I were to lose to desire, I would be sent to a tribunal meeting. But enduring on, refusing to succumb to desire was also quite painful. If following either path led to hell, then turning back would be the correct decision.
"Oooh, Mononobe, you're so malicious."
"I didn't say that because I'm malicious..."
I scratched my head, out of ideas. Right now, I was mustering all my effort to suppress my impulse. I was not confident I could withstand further stimulation.
I turned my attention back to the monitor, but things would be bad if I saw something I should not again, so I fixed my gaze on the screen that displayed the sea.
"I clearly wanted to reward you, Mononobe..."
Iris was murmuring in her lips, leaning her body against me. Through the sheer fabric, her body warmth was transmitting to me distinctly.
I looked for conversation topics to change the subject.
"I-Iris, what's that one screen that's showing the sea surface? The image seems to be moving, so it's not a fixed camera right—"
I rapidly asked Iris but her face instantly became shrouded in gloom.
"Oh... That seems to be the one monitoring Leviathan. Because the dragon can't be seen deep in the sea, it's right there—under the seawater."
I realized I had changed the subject to something bad.
"...Sorry, I made you feel worse."
"No. It's okay, because by doing this, I'll cheer up soon enough."
Smiling, Iris hugged my arm even tighter—


Just as Iris mentioned, when it was almost noon, a school nurse arrived.
Iris had changed into her school uniform. I accompanied her to the examination room but since I could not go in after all, I stood outside the door, waiting for the examination to end.
This was originally the first floor of the school building, but since it was now underground, all the windows were covered by metal shutters.
Because I had nothing to do, I generated some dark matter and practiced altering its form to pass time.
"I knew it, I'm still not used to guns weighing this light..."
I sighed and crushed the dark matter in Siegfried's form inside my hand. Then I heard footsteps approaching.
Someone was walking from the other end of the corridor. With long flowing hair, head raised, chest out, walking in a very prim and proper manner, she was—
"Mitsuki."
As soon as I called out to her, Mitsuki instantly stopped. This was our first time meeting since last night. I recalled what Lisa had said about what happened two years ago.
"Nii-san..."
"You need me for something?"
"...Yes, although I actually wish to avoid broaching this topic."
Mitsuki nodded with a gloomy expression.
"It's best to get unpleasant things over with quickly, right?"
I urged her by using a tone of levity.
"Good point... Well then, I have several questions for you, Nii-san. Did you use your full ability during the test last time?"
"Of course I did, Mitsuki. You saw during my training, right? You should know that's my limit."
Hearing my answer, Mitsuki continued to ask:
"So, according to your methods... Nii-san, without using fictional armaments, can you easily crush that block of diamond?"
"...No, I think I already demonstrated in the first training session. My method is to use an anti-materiel rifle and that's the most effective means."
I knew roughly what Mitsuki wanted to ask about.
So I prepared myself and waited for her to ask.
"Well then... Three years ago, Nii-san, how did you repel Hekatonkheir? Can you no longer accomplish the same thing?"
"..."
Finally. Ever since my reunion with Mitsuki, I expected to be asked this question eventually.
That day, I challenged "Blue" Hekatonkheir in order to defend the town—
"If possible, I have no wish to dig up what happened then. I would like to keep that incident buried in my heart too. You would probably be forced into an even more awkward position if that incident came to light. Because what you did that time was so unusual, a miracle so unbelievable, Nii-san, but..."
Mitsuki continued with a leader-like expression.
"As captain of the Dragon Subjugation Squad, I must maintain a grasp on all currently available combat potential. If incorrectly used or managed, strong powers have the potential to hurt oneself instead. I am very afraid, unsure of what you might do next, Nii-san, so—"
"I understand... I'll answer you honestly."
Because Mitsuki looked extremely sad, I interrupted her and nodded.
"...Sorry, Nii-san."
"No need to apologize, you're just doing what you have to do as the captain. About your question just now, my answer is no. Currently, I'm unable to singlehandedly repeat what happened three years ago."
"Unable to singlehandedly... Is that so? I see now. I can probably imagine the usage condition required back then."
Mitsuki said with a somewhat enlightened expression.
"That's so fast. But even if that condition is fulfilled, I probably still can't defeat Leviathan. That's what my power is like."
Three years ago, I ultimately failed to kill Hekatonkheir. Despite the heavy price I paid, it was still beyond me.
Precisely because of that, I found Mitsuki to be an extremely dazzling sight. Because destroying a dragon was a power that I could never possess, no matter how many more heavy prices I paid, I would still be inferior to Mitsuki.
"...I understand now. You have said enough."
Mitsuki exhaled lightly and nodded. Then she gazed into my eyes.
"If I raised your hopes up... I'm sorry. But even if I can't defeat a dragon, I might be able to help in some way. Because that power needs a stable footing, it can't be used from the air or on a ship. Because of that, even if I can participate in attacking, I think it'll have to be near the final defensive line—"
"No, there is no need, Nii-san, you only need to focus on protecting Iris-san. My goal was to ask you to avoid using that power as much as you can if concealing it was your original intention."
Mitsuki's response greatly surprised me. I thought she was hoping my power could defeat Leviathan.
"If I used my power... will something bad happen?"
"Yes, if I remember correctly, three years ago, Nii-san, what you used was a firearm-like weapon. If that type of weapon were to be used carelessly, not only will it fail to defeat Leviathan... Worse comes to worst, it might end up deflecting back."
"Deflecting back?"
"...You will understand once the battle begins. Please watch the screens in the shelter carefully."
Mitsuki turned her back to me after speaking.
"You're leaving?"
"Yes, because I still have a pile of work to do."
"I see... Don't strain yourself too much."
I actually wanted to ask about the girl named Shinomiya Miyako, but I could not bear adding more to Mitsuki's mental burden, so I swallowed my words.
"This I cannot agree. If I do not strain myself now, when else? I have promised to everyone at the full-school assembly—I will put my life on the line."
Rather than a sense of mission, her expression seemed to carry resolve of a more heavier nature. After saying this, she headed down a dark corridor to leave on the other side.
Unable to say another word, I could only see her off, watching that slender back that was shouldering so much.


"Ah, so tired..."
After the tests, Iris came to my side and stretched.
"Good work. Let's go back to the shelter for dinner."
Iris naturally put her arm around mine. While trying my best not to think about her body warmth, I walked over towards the elevator.
Then at the school building's entrance hall on the first floor, we met familiar faces.
"...Oh!"
The one who exclaimed softly was Firill. Ren and Ariella were by her side too.
Ariella raised her hand and spoke to us.
"You came at the right time. Because it's break time, we were thinking of heading to the shelter."
"To the shelter? Why?"
Hearing my question, Ariella frowned.
"What's so strange about visiting a classmate to see how she's doing?"
Next to her, Ren nodded frequently to concur, her red hair swaying.
"No, it's not weird at all. Sorry, I asked a pointless question."
Lisa had said that fellow classmates were equivalent to family. Ariella and the others seem to be holding the same sentiment.
Firill then approached Iris and peered at her face.
"...You look very exhausted. Are you doing okay?"
"Y-Yeah, I"m fine. It's just that the testing dragged on for too long, I'm hungry."
Iris answered with a nervous expression. She was probably unused to being treated so gently.
"...Really? Then please take this."
Firill handed a small bag of something to Iris. Accepting it, Iris opened it and immediately showed excitement on her face.
"Wow, it's chocolate!"
"...This is the chocolate I bought overseas through the internet, not too long ago."
"Eh? Then isn't it expensive?"
Hearing Iris, Firill nodded.
"Yes, but you can have it."
"...Thank you, Firill-chan."
Iris thanked her with tears in her eyes then Ren and Ariella also presented small gifts from the side.
Ren's was candy while Ariella's seemed to be cookies.
"Umm... Is it really okay for me to have this?"
Iris accepted them in trepidation and asked them.
"Mm."
Ren kept nodding with an expression that seemed to say "of course you can."
"I feel bad that I can only do this kind of thing for you, but tomorrow, I will fight my hardest to protect you."
Ariella spoke with a serious expression.
"Ren-san, Ariella-san... Thank you."
Iris was finally moved to tears.
"...Don't cry."
Firill passed her handkerchief to Iris.
Seeing that handkerchief, Iris found it even harder to stop her tears.
After a while, Iris finally stopped crying and everyone waved and took their leave. Watching their backs as I saw them off, I said:
"They're really great classmates."
"...Yeah."

"Mononobe, the bathwater is ready! Let's take a bath together!"
That night, after eating dinner and the snacks from Firill and the others, Iris regained her cheerfulness and suddenly announced.
The shelter instantly fell into a brief silence, because it took me a while to understand what Iris was saying.
"...I refuse."
I exhaled greatly. Evidently, Iris had completely failed to understand what I said this morning.
"You refuse to protect me in the bathroom? I'll be afraid if I'm alone..."
"Urgh..."
Seeing her show a worried look, I felt a bit guilty, but this was a line I could not compromise.
"...I'll be in the room. Just hang in there for now."
"Aww... Fine, then let's bathe separately. Mononobe, you go first. Since we're staying in the same room, I hope you'll wash yourself very clean."
Looking slightly displeased, Iris urged me to to take a bath.
"I don't mind going first, but why me first?"
"Because if I let you go after me, you'll lick the tub I used and drink the water I washed with, right? After all, that still would make me feel... embarrassed."
"Like hell I'd do that! Are you still looking at me in that way...?"
Hearing her say that, I walked to the bathroom, feeling hurt. Taking off my uniform, I entered the bathroom naked. The tub was already filled with hot water.
I sat down on a bathing stool then poured warm water over my head. At this moment, I sensed someone's presence in the changing area's direction.
"No way..."
I had a bad feeling. Looking up, I saw a white figure behind the frosted glass.
Before I could stop her, the door slid open and Iris entered, wrapped in a towel.
"M-Mononobe! I came to help you scrub your back! It's because I still wanna repay you—"
Her slightly nervous voice was cut off mid-sentence. Seeing my completely exposed naked body, Iris had her mouth opening and closing inexplicably—
"Kyahhhhhhhhhhhhh!"
Covering her eyes, she screamed.
"Don't go barging in without permission then scream! You've reversed our positions!"

I hastily covered up my crotch with a towel while grumbling at her.
"B-But... But..."
Her face bright red, Iris peeked at me through the gaps between her fingers.
Fidgeting awkwardly, she was rubbing her snow-white thighs together, exposed under her bath towel. That was too stimulating a sight. I hastily shifted my gaze away.
"Okay, hurry and leave. I'll shower then come out straight away."
As much as I wanted to drive her out by force, the towel I brought in was not enough to wrap around my waist, making it impossible for me to stand up.
"N-No way... I can't give up because of something like this."
Clenching her dainty fist in front of her chest, Iris shook her head.
Then mustering extraordinary willpower, she circled over to my back with stiff footsteps, then froze at this moment.
"Hey... Mononobe."
"W-What?"
I answered nervously.
"Back scrubbing... How do I scrub?"
"You... You wanted to help me scrub without knowing how?"
I asked in exasperation.
"I only heard that this kind of custom exists in Japan... I don't actually know the details. Do I just pour hot water over you?"
"Pour hot water, then use a soaped towel to scrub... I think that covers it."
"Eh!? I didn't bring additional towels! M-Must I untie this one?"
Iris was just about to untie the towel wrapped around her body.
"No need to untie! Just use your hands directly if you don't have a towel—No wait, you don't need to do this at all, now that I think about it. Get out now!"
"No need to be shy, Mononobe, because I'm not forcing myself to do something I dislike."
Saying that, Iris rubbed her hands together to make the soap lather, then started washing my back.
"Woah!?"
Feeling someone else's touch on my back was more ticklish than I imagined.
"Fufu—Mononobe, you shuddered."
Initially a bit inexperienced, she gradually grew bold. Because she seemed like she was not going to give up no matter what, I decided to indulge Iris until she was satisfied.
"Monobe, your back... is so wide."
"..."
Iris' little hands, which were scrubbing my back, made me realize again the fact that she was a girl.
To be honest, it did not feel unpleasant at all, but... Suppressing instincts continuously was extremely taxing for the mind. When I promised Mitsuki I was not going to engage in inappropriate interactions between genders, I never expected this kind of predicament at all.
Rather, this could be considered "inappropriate" already, right?
Although such a thought crossed my mind, I still told myself that it should still count barely within bounds.
"It's not very visible under clothing, but your muscles are quite firm. It's unexpected."
"...Well, that's because I went through training in the army."
"Is that why? ...Training must be tough, right?"
"Yeah, I almost died."
"Thank goodness you didn't die, Mononobe."
Hearing Iris' almost nonsensical response, I could not help but smile wryly.
"What are you smiling for?"
"...It's just a bit ticklish."
"Oh, then I'll wash the front next."
Perhaps deciding that the back was washed enough, Iris circled around to my front.
"Hey, that's no good! Iris, you came to scrub my back, right? In that case, I don't need you to wash the front!"
"Consider it a freebie! A freebie! Don't be shy, Mononobe."
Iris smiled at me innocently.
"I'm not being shy... W-Washing the front yourself is part of manners!"
"Manners? It's true, I definitely haven't heard anything about a custom of washing the front..."
"That's right, the back is the only part you can entrust to others. You've heard of the saying, 'letting others cover your back,' right?"
"Y-Yeah... But it feels like you're using twisted logic..."
Iris looked up at my face from below. The cleavage visible from her bath towel was shaking my sanity.
If I allowed her wash my front in these circumstances, an irreversible situation was going to develop.
I desperately persuaded Iris, finally convincing her with much difficulty.


However, there were even harsher trials awaiting me that night.
"Mononobe... Let's sleep together tonight."
Seeing Iris invite me to bed while dressed in a sexy nightgown, I felt my consciousness leave me for an instant.
"Tonight... might be my very last, so to me, this may or may not be my final remaining time... I don't want to spend it alone."
—That was such an unfair way of putting it. How could I possibly ignore her?
But even so, I desperately tried to resist.
"Can't you ask someone else? For example, if it's Lisa—"
"I prefer you, Mononobe, I don't want anyone else! This is my request of a lifetime!"
"How can you make unreasonable demands like a child...?"
"I don't care if it's an unreasonable demand! If my life is ending tomorrow, then it's too much of a waste if I don't use up my request of a lifetime now!"
I realized what Iris was trying to convey really was "a request of a lifetime" literally.
"Why... are you choosing someone like me?"
Unable to comprehend this, I asked her.
"—Because you've treated me with kindness."
"Huh?"
"Because you've treated me with the most kindness, Mononobe. You're the first person to extend a helping hand to me. If you must ask for a reason, that's pretty much all I can answer. Is this kind of reason... not enough?"
Seeing her ask me with tears in her eyes, I could not help but take a few steps back.
"No... Nothing like that—"
"Please, I beg you, Mononobe, even if it's just lending me your back for me to lean against, aren't backs for entrusting to others?"
To think she was bringing up the excuse I had used in the bathroom, I had no choice but to surrender.
"...I got it. If showing my back to you is fine, I'll stay with you, Iris, until you fall asleep."
I prepared myself, climbed onto the bed and lay down with my back facing her.
"Thank you... Mononobe."
Iris leaned herself against me and whispered in my ear. The softness and warmth I was feeling against my back was making my consciousness boil.
Surrounded by sweet fragrance, my rationality was almost flying away. Despite the fact that we were both clearly clothed, it felt even more dangerous than in the bathroom.
"So this is your scent, Mononobe... I knew it, the real thing is better..."
Iris pressed her face against my clothing, murmuring to herself.
"...Real thing?"
"Eh? N-Nothing, d-don't mind me."
Behind me, Iris was especially flustered.
"Speaking of which, the shirt I lent you the first time we met... What happened to it?"
"Frightened!?"
"...I've never heard anyone yell 'frightened' as an exclamation before."
I smiled wryly as I spoke.
"N-No! I didn't take the shirt to sniff it, to hug against my bosom, or use it as sleepwear!"
Iris argued in quick succession to defend herself.
"...I never knew you were that perverted."
"I said I didn't do it! If you must have it back, I'll return it next time. I'll even give you special permission to sniff and lick it out of my sight."
"Like hell anyone's gonna do that! Besides, that was mine to begin with. I don't have any weird fetish of getting aroused from my own clothing that someone else had worn! Returning the shirt is only going to cause me a headache. You can have it as a gift!"
Although it was no big deal, I had no desire of wearing something that I had no idea what had been done to it.
"...Thank you! Sure enough, you're so kind, Mononobe."
"Uh, if you say I'm kind for something like this, you'll only give me a headache..."
Because what I said totally did not stem from kindness, I had no idea how to react.
"No, Mononobe... You're very kind... Extremely kind."
Saying that, Iris leaned even tighter against me. Two soft sensations could be felt pressing against my back more strongly.
"I-Iris, it's touching me! It's touching!"
Although accusing her like this did not feel proper, at this rate, my rationality really was going to reach a limit, which was why I yelled at her.
"Yeah... I know"
But Iris remained unfazed. Quietly, she spoke:
"Mononobe, there are three ways to prevent a D from turning into a dragon. The first is to defeat the dragon. The second is death. And the third is... to stop being a D."
"That's—"
I recalled the conditions Mitsuki had mentioned about Ds losing their power. Instantly, my heart rate jumped.
"That's right... Reaching twenty years old or so, or getting pregnant, that's how we become ordinary people, so—"
Iris whispered softly in my ear.
"S-So...?"
"..."
I asked her but Iris did not answer.
She simply pressed her fiery hot body tightly against me.
The sound of heartbeats seemed to be pulsating next to my ear. My mind went blank.
In this quiet room, all we could hear was each other's breathing.
Unable to say anything or do anything, I could only let time pass like this.
My sanity was getting worn away bit by bit.

But just as I was about to reach my limit, Iris laughed from behind.
"Sorry—Saying it that way was a bit underhanded just now."
"Huh?"
"...Actually, even if Ds get pregnant, their power weakens gradually rather than losing it all at once. It takes roughly three months for a D to lose her power completely, so it's too late once you're targeted by a dragon."
"Don't say such things that'll make others misunderstand..."
I almost lost control because of that.
"Fufu, Mononobe... Your heart was beating so fast just now, because I had my ear against your back, I heard it clearly."
"...I heard your heartbeat too, Iris."
"Ehhh! No way!?"
Iris began to panic behind me.
"If you're leaning so close, of course I'll hear you. Also, if you're going to play pranks like earlier, I'm going to sleep on the floor or outside."
"Oh... S-Sorry! Mononobe, please don't go!"
Iris grabbed me desperately.
"H-Hey!"
"I'm not going to play a prank... I just wanna say... If you really want to do that, Mononobe... But halfway through, I felt afraid again."
"Oh come on... Maybe you're trying to repay me again, but that's going way too far. If an accident happened, you might lose the power to fight dragons, you know?"
Iris felt a strong sense of duty towards the matter of fighting dragons. She trained desperately to hone her power for the test. I did not want her to give up on that power so easily.
"But... If I die tomorrow, it doesn't matter..."
"Rather than thinking about the case of dying, it's more constructive if you think about the case of surviving."
"That doesn't sound like something coming from the one who promised to kill me, you know...?"
Iris spoke in a tone of disagreement.
"Yeah, on the one-in-ten-thousand chance of that happening, I will kill you before you turn into a dragon. But you've got to try thinking about the rest of the ten thousand, right?"
"The rest of the ten thousand?"
Iris did not seem to understand, so I continued:
"Suppose the total is ten thousand, after taking out that one chance, there are nine thousand nine hundred and ninety remaining, in other words, that many futures where I won't have to kill you, Iris."
"You're just playing word games."
Iris disagreed quietly.
"Really? I think that's how high the chances are. Mitsuki, with her accomplishment of having defeated dragons, is also standing on our side. You should put a bit of faith in my little sister at least."
I said cheerfully without looking back. Although half of what I said was bluffing, the remainder was serious.
I could feel Iris' arm relaxing, followed by a tiny laugh.
"Fufu—How unbelievable. After hearing that from you... Mononobe, I'm beginning to feel that perhaps you might be right."
"In that case, sleep earlier tonight. This is for the sake of tomorrow—and beyond."
I felt her nod in agreement.
"...Yeah, goodnight, Mononobe."
"Okay, goodnight—Iris."
Soon after I responded, I could hear the breathing from her sleeping soundly. Perhaps she had been unable to sleep the previous night.
Because Iris was still clinging to me tightly, I could not even get out of bed quietly.
Despite acting cool earlier, I was still bothered by the warmth and suppleness of Iris' body. It was impossible to sleep at all.
Fighting a protracted war of resistance from then on, I only fell asleep just as dawn approached.