Prologue: Faded Childhood Memories
Now it was just a blurry memory from his childhood. He'd once watched an anime with his uncle. Though he'd forgotten the title, the content had lodged deep in a corner of his mind. The protagonist, your typical ordinary high schooler, suddenly gets chosen as a pilot and fights mysterious monsters in a giant robot defending his city.
Honestly, it wasn't that entertaining. If anything, it was frustrating. In modern terms, it was stuffed full of those aggravating plot twists that peel like sweet potatoes. Whether it was for the sake of plausibility or not, the protagonist-turned-pilot was as average and immature as any common high schooler, and as emotionally volatile as a hormonal teen.
The reason that childhood viewing stuck so vividly in his head even now was probably that frustration he'd felt back then. But now, at least, he could sort of understand it. Suddenly piloting a war machine into battle without knowing a damn thing about it—turns out it's not as easy as it sounds. Especially when you're not fighting alone, but as a pair: man and woman.
"Haa... haaah..."
A girl's ragged breathing suddenly brushed his ear. The young man, lost in thought, slowly lowered his gaze.

There lay a bob-haired girl sprawled over a space like a motorcycle cockpit. And he was pressed against her lower body, gripping the control stick linked to her mana nerve system.
It was a pose that evoked rear-entry, quite provocative, but sadly, there was no sweet intimacy between man and woman in this cramped confines. Just the tension of not knowing when death might strike.
It had to be that way. Right now, the two of them were locked in a life-or-death battle with the enemy, piloting what was commonly called a Holy Knight.
"Ngh... S-stop..."
Was it the strain of the prolonged fight? Though her face wasn't visible, sweat beaded thickly on the girl's pale white nape. It flushed as red as her frantic breaths, her disrupted breathing refusing to settle as it lingered in the air.
Then—
Screeeeech...
A repulsive noise echoed nearby, and something hideous resembling a spider appeared. One of the monsters commonly known as a bug.
The young man immediately spotted the enemy's movement. Without hesitation, he gripped the control stick connected to the girl's mana nerve system and maneuvered the Holy Knight.
"...Kyaaaah!"
Her body, already pushed to its limits long ago by the endless combat, couldn't hold out against the Holy Knight's sudden acceleration. The girl finally let out a scream she couldn't suppress.
But the young man had no intention of handling her gently. The enemy was charging right at them this instant. Any misplaced pity or softness here, and they'd be the ones dying.
Ignoring her screams and gasps as much as possible, he surged forward. It looked like a reckless charge, but it was a rational judgment.
Bugs came in all shapes and sizes. The one before them now was nicknamed Spider—a tank-like beast with a cannon mounted atop its spider-like body, firing shells.
Its ranged attacks were certainly threatening, but thanks to its nature, closing the distance made it easy to take down.
In an instant, he'd narrowed the gap. With the Holy Knight's sword, he slashed the Spider's torso.
Fortunately, the Spider's defenses weren't anything special.
Schluck—!
Was it because he was linked to the Holy Knight through the girl's mana nerve system? The vivid sensation of the blade cutting through confirmed the Spider's death for him.
And just then, as blood gushed from the Spider's diagonally severed torso—
Finally over. The young man released his grip on the control stick linked to the girl's mana nerve system. Tension draining from his body, he lowered his gaze again.
There she was, collapsed atop the cockpit like she'd passed out from exhaustion.
Had she lost consciousness the moment the battle ended? He stared at her blankly for a while, then leaned back against the cockpit seat.
The commander's return order had come, but there was nothing for it now. To move the Holy Knight "normally," he had to wait until she regained consciousness.
So he decided to close his eyes and rest a bit. Lamenting this godforsaken anime world.
A world where men and women had to pair up to fight—this uncomfortable setup really didn't sit well with him.
To pilot the bio-operated weapon known as the Holy Knight, a young man and woman must pair up. Pilots commonly called this coupling.
And that was the core setup of the last anime he'd watched.
On the way back to base.
"...Coupling, my ass."
The young man let out a hollow chuckle. A line from an anime PV he'd seen on YouTube popped into his head.
Boys and girls who lean on each other to fight and save the world from monsters.
That's the catchphrase the director had flaunted in the PV. But honestly, what bullshit was that?
Sending kids into bio-weapons called Holy Knights to battle invading forces—is that even a sane setup? Sure, it's acceptable in an anime, but if it were reality, it'd be a total dumpster fire. Basically, child soldiers, right?
As he stepped down from the Holy Knight, pondering the same doubts he'd mulled over the past few years—
Slap—!
The slap rang out crisply. An unexpected hand whipped his face hard to the side.
The young man slowly turned his jaw back and looked ahead.

"..."
His cheek stung fiercely. She'd probably swung without holding back. The heat of pain prickled sharply at his skin.
He could've dodged, but he took it on purpose. He'd seen this reaction coming.
If a single slap could vent her rage, it was a bargain. So he met the owner of that fiery hand with calm eyes.
"You really..."
Before him stood a girl glaring with eyes red and bloodshot, on the verge of tears. It was the girl who'd coupled with him for today's bug battle.
Her lips trembled as if searching for words, then she spat them out laced with fury.
"...You're trash who treats your partner like an object."
As if she couldn't stand looking at his face anymore, she spun on her heel. Sadly, one slap hadn't quenched her anger—each step away seethed with rage.
A pilot's fallout was plenty to draw eyes. In an instant, gazes converged on them.
The women's stares especially stung. Disgust and contempt shone plainly in their eyes.
Probably from today's incident and the rumors about him.
He glanced idly around, amused, and nearby male pilots started shielding their own partners with their bodies. As if even his gaze on their women creeped them out.
The young man just let out another hollow laugh at that.
It had been years since he'd fallen into this godforsaken world. He was used to it by now, but it wasn't exactly a pleasant sight.
He wasn't some pervert who got off on hatred and scorn.
Whatever. Amid the gathered stares, he slowly rubbed his slapped cheek.
Apparently, the intensity of today's battle had been too much for that girl. Well, he'd been testing her limits, handling her like a tool—couldn't be helped.
But they'd won, hadn't they? They survived. Claimed victory in the end.
Way better than ending up a breathless corpse dumped on the roadside like trash.
Maybe, just maybe, someone lived because of him.
He stood blankly until the girl vanished from sight, then turned his head.
Through the glass, he saw the results of today's battle: ruined cityscapes, shattered roads. And scattered around them, countless grotesque lifeforms.
Their numbers easily topped a hundred. The otherworldly "invaders" commonly called bugs. Or more precisely, living bio-armored weapons.
After quietly observing the things he'd fought who-knew-how-many times, amid the pilots still glaring at him, the young man turned away.
