A Father's Resolve
The researcher's voice carried a note of genuine awe. "Every time I review the data, I'm amazed. Yuto's numbers are tracing an increasingly sharp upward curve."
Hideyo offered a sheepish smile in response. Having such a son right beside him all this time, only to have completely missed his talent, left him feeling nothing but embarrassment.
"At this rate, the complete coupling model we originally designed—one based on the bond between man and woman—might actually become reality. We're already seeing data like this... I can't even imagine what will happen once he accumulates enough experience."
The very concept of Coupling had been developed from the beginning with the bond between man and woman as its premise. The woman, as Bottom, would handle the delicate manipulation of the machine, while the man, as Top, would take the lead in reading the flow of battle and making strategic decisions. That was the ideal coupling system the original research team had dreamed of—the perfect model.
But the more experiments they ran, the more male-female coupling kept failing due to synchronization errors and sensory mismatches. In contrast, coupling between women showed exceptionally high response rates and produced the only meaningful results. As a consequence, the female-to-female coupling system had become the mainstream—completely contrary to the original design.
If only I'd realized Yuto had this kind of talent sooner...
Even by Hideyo's own assessment, Yuto's adaptability was beyond imagination. Just a few days ago, his synchronization rate had climbed so high that his body had connected to the Dracore at a depth it could barely withstand. It was astonishing that such results could appear after he'd only just begun piloting a Dracore.
If they'd discovered this talent even a little earlier, they wouldn't be rushing through the research schedule like this, constantly chasing experimental data.
"By the way, Dr. Hideyo. When do you plan to review additional partners for Yuto? It seems the higher-ups are starting to suggest reviving some of the old experiments again."
"...You mean the proposal to reactivate the Tebe Model?"
"Haha, of course the context is a bit different this time. The Tebe Model was ultimately based on romantic affection between female pilots, after all."
The Tebe Model had been designed around the motif of the ancient Greek 'Sacred Band,' under the assumption that deep emotional bonds could maximize combat capability. Theoretically, the emotion required to reach the absolute threshold of coupling was considered to be 'romantic love.' In practice, strong affection and obsession toward one's partner had consistently been analyzed as the core elements for achieving perfect synchronization.
However, the Tebe Model's limitation had ultimately been the structural instability inherent in same-sex romance. While emotionally viable, it struggled to replicate the instinctive, natural flow of emotion found in heterosexual love. Simple emotional synchronization between members of the same sex could not reach perfect coupling, and those tiny gaps became the system's ceiling.
"I know this would be burdensome for both you and your son, Doctor. But as you know, Yuto's talent is no ordinary gift. If things go well, he could become the most powerful pilot in history."
So far, the results had shown that female-to-female coupling alone could not reach the absolute threshold. But what if it were coupling between a man and woman who had fallen in love? That was the possibility every researcher was now watching most closely. Especially when it came to handling the 'special power of the Outers' latent within the Dracore.
"...When I get home, I'll talk with them again. Calmly this time."
Hideyo gave a light nod and let out a sigh. A swirl of complicated emotions rose up at once, clouding his eyes for a brief moment.
Father sat perfectly straight, not a single strand of his posture out of place. His gaze was calm, yet it pierced straight through me. This moment felt like a punishment that wouldn't even let me breathe properly.
It was as if everything that had happened just moments ago at the front door had been nothing but an illusion. The heat, the impulse, even the sensation of her lips—all of it felt like a meaningless transgression at this dinner table.
Yuzuki, sitting beside me, said nothing. She kept her head lowered, simply breathing. The house was so quiet that even her small breaths sounded crystal clear.
"...Explain yourselves."
Father's voice was low, but there wasn't the slightest tremor in it. I lifted my eyes. His gaze remained fixed on my face. Though it looked emotionless, something was clearly flickering deep within.
It wasn't a question. It was confirmation. He wanted me to say the truth he already knew out loud.
"......"
But the words wouldn't come right away. My mouth went dry, and my heart beat awkwardly.
"...Was what the two of you just did a simple mistake... or..."
Father seemed unable to finish the sentence, so instead he used his eyes to demand my answer.
I glanced sideways at Yuzuki. Her face had gone deathly pale, and she was clutching her fingers on her lap so tightly it looked painful. Yuzuki was terrified. It wasn't simple embarrassment or shame. She had completely frozen in place.
This was something I had to bear. After all, what fault did Yuzuki have in any of this? I was the one who had done it.
I raised my head again. Father's gaze was still coldly slicing through me, but this time I didn't look away.
"...I was the one who kissed her first."
The moment I spoke, Yuzuki drew in a small, sharp breath beside me. I didn't turn to look, but that reaction alone was enough. I kept staring straight into Father's eyes. Whatever judgment he made, whatever price I had to pay—this was something I had caused.
Father squeezed his eyes shut tightly, as if he'd heard something he wished he hadn't.
"...Since when have you two been in that kind of relationship?"
My mouth felt parched. After a long pause, I finally managed to answer.
"...I'm not sure exactly when it started."
I lowered my head slightly and continued slowly.
"But... after our first coupling, I felt that something between us had changed. It took me some time to admit what that feeling was... but now I know for certain."
I looked Father straight in the eyes and spoke the final words.
"...These current feelings are my own will."
Father remained silent. For a moment, his eyes trembled faintly. Then he turned his head ever so slightly, avoiding my gaze, and repeatedly clenched and unclenched the hand resting on his knee.
"...So in the end, through coupling, love for each other blossomed. Is that what you're saying?"
His voice was low and dry, but the emotion clinging to the end of his words was pure suppressed agony. Whether it was resignation or self-directed anger, I couldn't tell. The weight of it pressed down even heavier on the air above the table.
"...Yeah. B-but... it's not just because of the coupling..."
This time it was Yuzuki who answered. She lifted her lowered head and carefully met Father's eyes.
"...Lately, I've just been constantly aware of my brother. I don't really know why... but he keeps catching my eye, I keep wanting to see him... and before I knew it... I just... fell for him."
"...So the coupling became the trigger, after all."
"W-well... I guess you could say that..."
Yuzuki's voice trailed off, as if she had suddenly become aware of how real the feelings she'd spoken aloud truly were.
Father slowly closed his eyes, then opened them again.
"As you both know, coupling isn't just a technology. It's a process where not only senses, but emotions and egos penetrate each other."
He lowered his head just a fraction as he continued.
"Once emotions have mixed, they can't easily be separated. That's why we should have been more careful. We should have noticed sooner... It seems I learned that lesson far too late."
His voice trailed off into a quiet sigh. The words that followed sank low and deep, like self-reproach directed at himself.
"When I think about how your relationship changed in this way because of coupling... it weighs on me too heavily. In the end, all of this is my responsibility."
Father murmured softly.
"I only thought about getting good research results. I turned a blind eye to what you two might be feeling, how you might be shaken..."
For a moment, it seemed as if his throat had closed, but he soon continued.
"I really only knew how to stare at research data. I couldn't even properly look at the family right beside me."
He gave a small laugh. But it wasn't a laugh at all. Only the corners of his mouth lifted while his eyes remained hollow, and regret and exhaustion etched themselves along his jawline. A guilt too heavy for words was slowly crumbling beneath that quiet smile.
How long did that heavy silence stretch on?
"...I won't stop you two."
"What?"
"Dad...?"
At Father's unexpected words, our eyes widened in shock.
But then—
"However, there are conditions."
Father straightened his back once more and met our eyes clearly. Within them, the weight of a father and the resolve of a research director coexisted.
"Even if Yuzuki doesn't want it, Yuto must date other women and perform coupling with them as well."
Yuzuki's shoulders trembled faintly. Her eyebrows, which had been fixed on the table, twisted into a frown. She jerked her head up as if she'd been slapped.
"...What? What are you saying, Dad?"
The confusion and suppressed anger in her voice scattered into the air.
Father looked at her quietly. His gaze didn't waver.
"Yuzuki. This is what I told you the other morning as well."
"...The other morning? You mean... when you said the government wants to increase the number of pilots?"
"Yes. I don't know how you took it back then... but the government is taking it very seriously now."
His tone remained firm, but his eyes had sunk deeply somewhere.
"Starting today, research into expanding aptitude based on Yuto's coupling patterns has officially begun. The correlation between emotion, disposition, and feedback is now the highest priority observation item. The reason I didn't come home yesterday was because of that."
"..."
Yuzuki couldn't say anything. She simply breathed, her face showing someone trying to forcibly accept something she didn't want to understand.
"Therefore... we want to determine how romantic love, deep attachment, or any such emotions between man and woman affect Dracore piloting. In a way, that was the true goal of coupling from the beginning."
Yuzuki blinked a few times, then spoke in a faint voice.
"...Then you can just use the data from me and my brother."
It was a short, simple statement, but it carried clear resolve.
Father lowered his gaze for a moment before answering in a low, quiet voice.
"Do you really want that?"
The question carried a heavier reality than any explanation could.
"No matter how much I acknowledge you two, if we do that, your relationship will be officially 'recorded.'"
He paused for a beat before continuing.
"All that data will be compiled into reports, reviewed by hundreds of researchers, discussed in meetings, and published as academic papers. Your emotions, your actions, even the heat of those moments—they will all remain there, exactly as they are."
Yuzuki drew in a tiny breath. Only now did she seem to grasp the true meaning; her head dropped.
This wasn't simply being found out by Father. It would be the same as exposing everything to the entire world.
"I don't even want to imagine how the world would look at you two after that."
For the first time, that statement carried the broken emotion of a father.
The day passed in a blur. I'd gone on a date with Yuzuki, kissed her, and then been caught by Father right there. Yuzuki's trembling expression, the suffocating silence that had pressed down on the dinner table—everything tangled together in my head. Even now, as I lay in my room staring at the ceiling, I couldn't sort it out.
Lying on my bed, I stared blankly at the phone in my hand. The screen kept turning off and on again, but nothing appeared on the lock screen.
Yuzuki hadn't come out of her room even once since she'd gone in. If the night passed like this, it felt like something irreversible would be left behind.
So in the end, my fingers moved first.
The wait was long. In the dark bedroom, beneath the silent ceiling, the phone in my hand felt unusually heavy.
After a while, the screen vibrated.
Those two short words made me feel like my breath had stopped. Was it just my imagination that I could picture Yuzuki crying somewhere in my mind?
When I'd turned around that moment, Yuzuki had been looking up at me with eyes full of fear that we'd be caught—yet also filled with some kind of certainty. That expression and those eyes had been breathtakingly beautiful, and at the same time, cruel. Her anxious breathing and hesitant gaze had gently shattered the last shred of reason holding me back. In the end, the line I'd barely been clinging to collapsed without a sound.
Of course I know. I know how far this relationship has strayed from normal, and how unacceptable it would be to the world. And yet, strangely, I don't want to let her go any more than I already have. Maybe that moment was the first time in this world that I truly fell in love with someone.
In that sense, the fact that the person is now my little sister... it doesn't feel that important to me anymore. After all, I am Yuto, but at the same time, I am not Yuto. Even if Yuto's memories exist in my head, the self I am now is not him.
Of course, if the world saw it, they'd know how dangerous these feelings are and how full of excuses they sound. But pushing Yuzuki away now feels even more irresponsible. And I'm not even sure I could push her away anymore. Not after we've gotten this close.
In the end, I made the decision first.
This world has already begun to shift little by little because of me. In the wake of words that can't be taken back and choices that can't be undone...
Whatever. Since it's come to this, I might as well see it through to the end.