Shirou moved like a shadow in moonlight, silent and sharp-edged, barely a whisper on the cold stone floors of the underground research facility. The flickering torches in the corridor didn't flicker from wind—there was none down here—but from the chill of dark magic woven into the very walls. Somewhere above, alarms blared faintly, like distant wails of a dying creature.
The facility had been thrown into chaos since his escape—guards barking orders, boots stomping, cloaks rustling in frantic patrols—and yet, for the first time since he'd awoken in this dreadful world, Shirou's thoughts were clear.
The corpse of the priest was hidden carefully behind a stack of storage crates, limp and forgotten like discarded robes. Shirou had not wanted to kill, but some enemies made mercy an impossible choice. Now, cloaked in the priest's white robes—trimmed hastily to fit his more compact frame—Shirou could move unseen, aided further by a concealment charm Rin had taught him after a week of maddening practice.
It shimmered faintly about his body, like heat over stone, bending the light just enough to trick the ordinary eye. Unless someone had enchanted sight or magical tracking, he was little more than a ghost in the wind.
The guards outside the room were clustered near exits, yelling to each other in clipped tones, clearly expecting him to bolt. But Shirou didn't run. He slipped inward—towards the heart of the sanctum. That was where the true horror lay.
The Inner Sanctum was nothing like the outer corridors. It opened into a massive chamber—circular, dark, and filled with the echoes of screams long past. It was an arena, but no place of sport. A testing ground, they called it. A monstrous theater where summoned creatures, twisted by experiments, were thrown against terrifying beasts for the entertainment—and more disturbingly, the research—of the White Sacrament.
The stench was unforgettable: blood, sweat, despair, and the coppery scent of old magic gone foul. Shirou's jaw clenched as he moved through the area, passing the high stands where robed figures once observed like immortals from above.
They had made the humans fight. Ordinary people. Summoned like him, but weaker, unprepared, discarded after a few screams and splashes of red on the stone floor.
And still, they called it research.
A cruel hierarchy was at play in the Ark Continent. The White Sacrament, self-proclaimed bringers of purity and divine order, held dominion over kings, over borders, over lives. To them, anything not of their world was an "Outsider" — to be broken, enslaved, or erased.
And now he understood. The White Sacrament wasn't just a government. It was a cult armed with soldiers, scholars, and monsters of its own making. Its Apostles—the White Lord's chosen—were said to be living weapons, beings who could reshape the world with a single word or gesture.
That was who would come if Shirou was caught.
He pressed forward through the narrow stone corridor connected to the arena's back gates, past the iron-barred doors leading to the prisoner's wing. The air grew heavier, thicker. Pain hung in the air like perfume. The cages on either side were mostly empty now—some bore dark stains, others broken chains—but there were no cries, no moans. The silence here was absolute, and it was worse than screaming.
But then, as he reached the final row, he saw it.
A single figure remained.
The man—no, the boy, Shirou realized with a twist in his gut—sat motionless in a narrow cage of stone and silver. His expression was blank, eyes dulled by whatever torment he'd endured. Upon his head rested a cruel circlet of iron, studded with sharp spikes that pricked into his scalp, forcing compliance through pain.
Shirou stopped.
He crouched slowly, inspecting the boy through the bars. There was still life in him, but barely. A heartbeat, shallow and fluttering like a bird in a storm. His limbs were thin, starved of nourishment and sun.
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The boy did not stir. His body remained seated upright, like a discarded marionette with its strings sloppily cut. Shirou's breath caught in his throat. There was no light behind those eyes—no flicker of soul, no spark of rebellion. Just hollow, unblinking blackness.
It wasn't exhaustion or fear anymore.
He was broken.
Something inside Shirou twisted violently at the sight. Not just because of the horror that had unfolded here, but because of the calculated cruelty—the methodical stripping away of humanity. This boy, clearly once strong, proud, and defiant, had been turned into an empty shell. A vessel.
And he was not the only one.
The cages around them stood silent like tombs, and the message was clear. These were the failures. The successful ones—the ones whose minds had been twisted beyond recognition, the ones with power—had already been moved. Likely weaponized. Likely marching under the Sacrament's banner even now.
Shirou's hand clenched into a fist.
He stepped closer, taking in the boy's features. He was older than he looked at first glance—maybe twenty, tall and solidly built, with black hair cropped messily and a jawline that suggested he'd once been a fighter. His hands bore the calluses of someone familiar with hardship, his muscles taut under the grimy rags he wore. Despite the ruin of his mind, Shirou could tell this one had been strong—maybe even a hero once.
And Japanese. Without even exchanging a word, Shirou knew it. Just like the others.
Why was it always people from his homeland? What twisted summoning spell had bridged the worlds and dragged so many unwilling children, students, and warriors into this nightmare?
It wasn't just wrong.
It was a violation of everything magic was meant to be.
He needed to stop it. Somehow, he had to find the source of the summoning and destroy it, or seal it away forever. Because if another innocent arrived here—like Sakura, or Sella, or even Illya…
He didn't finish the thought.
For now, he had to act. The boy in front of him wasn't dead. Not yet. But he was close.
The circlet on his head—the cruel spiked ring pressing into the skin—was enchanted, that much was clear. It hummed with sickly power, reeking of mind magic, pain magic, perhaps even soul-binding. Removing it by force might kill the boy. Leaving it on would certainly do worse.
I'll take the risk.
Shirou inhaled sharply and reached within himself.
The air shimmered around him as his Reality Marble—the Unlimited Blade Works—rippled beneath his skin like a muscle flexing. From within that boundless forge, where a thousand weapons stood in eternal silence, he summoned a single blade.
Not just any blade.
Rule Breaker.
It slid into his hand like a memory, small and delicate, like a ceremonial dagger. But its edge shimmered with deadly promise. This was the anti-thesis of magic. The blade that denied curses, severed contracts, shattered enchantments. It had once nullified immortal pacts—this would be a whisper in comparison.
He moved fast.
Before anyone could raise the alarm, he darted back toward the corridor and cut down the nearest guards—three in total. Each fell wordlessly, their blood vanishing into the shadows of the arena. Then, as quickly as he had appeared, Shirou returned to the boy's cage.
Steel bars fell away like butter under Rule Breaker's touch.
He stepped in, crouched low, and without hesitation brought the glowing blade to the cursed ring. With the precision of a surgeon and the urgency of a storm, he slashed.
The ring split with a faint crack and fell to the floor with a dull clang.
At first, nothing changed.
Then, the boy's whole body jerked.
He collapsed forward, curling in on himself as if some invisible hook had been yanked from his soul. His fingers clutched his skull and a groan escaped his lips—harsh, guttural, and filled with pain. But it was real. It was human.
His eyes squeezed shut.
Tears leaked from them.
Shirou dropped to his knees beside him, catching his weight before he hit the cold stone.
"It's over," Shirou whispered. "You're free now."
The boy didn't answer, but the blankness was gone. In its place, there was agony, confusion—and most importantly, life.
----------------------
The silence spell shimmered like a translucent dome over the ruined cage, muffling the boy's agonized screams as they echoed soundlessly within the warded space. Shirou stood still, one hand loosely gripping the Rule Breaker blade at his side, watching as the young man thrashed, clutching his head as if trying to tear something unseen from within.
Pain twisted his features—real, visceral pain—the kind that came not from wounds to the body but from something deeper. From the soul.
Then, slowly, the screams faded. Replaced by heavy, shuddering breaths.
The boy's dark eyes snapped open, wild and brimming with rage. He fell to his knees, fingers digging into the stone floor, jaw clenched so tight it looked as though his teeth might shatter. The magic coiled around his arm like a viper, forming, pulsing, desperate for a target.
His lips parted, trembling with the effort of forming words. His throat, long unused, rasped with hoarse fury.
He had remembered.
Everything.
He had been taken. Torn from an ordinary, peaceful life—his life—and thrown into this monstrous place. He had been experimented on like a beast, mutilated, reshaped, and most damning of all—forced to kill. Other humans. Strangers. Perhaps even those who had once looked just as terrified as he had. His hands were stained, not by choice, but by compulsion.
Half a year.
Half a year of silence, numbness, and darkness.
And now his mind had come rushing back all at once, a tidal wave of memory and madness. The spell was broken. The drone was gone.
Only the survivor remained.
Shirou took a cautious step forward.
The magic flared in the boy's hand.
"Wait—I'm from Japan too."
The words were firm, clear, and immediate. They cut through the haze like a knife.
The young man froze.
He turned his head sharply, dark eyes narrowing on Shirou's face. His gaze flicked to the white robes—stained now with blood and dust—and for a brief moment, the fury rose again. The uniform. The resemblance. He had almost—
But then he paused.
Really looked.
And saw it.
The familiarity in Shirou's features. The color of his hair, the shape of his eyes, the cadence of his voice.
"…Who… are… you?" he asked, each word an effort, his voice rough like cracked glass. It wasn't just the months of silence—it was the trauma. The brokenness. The very act of speaking now felt foreign to him, like using a limb that had long since atrophied.
Shirou softened his stance and crouched slightly so they were at eye level.
"I'm Shirou Emiya," he said gently. "I was summoned to this world too. But I'm a mage—even back home. I broke free of their control. And now… I'm here to help you. You're not alone."
-----------------
The words drifted around Kurono like smoke—heard, but not truly absorbed. His mind was a maelstrom of images and sensations: pain, flashes of light, screams he didn't remember uttering, faces twisted by fear or cruelty. Reality was returning far too quickly, and yet not fast enough. He could feel himself waking, but not yet understand what that meant.
He blinked slowly, dazed, and raised a hand to his chest.
"…Kurono," he said at last, the name falling from cracked lips like an old spell. He tapped his chest twice, as if to remind himself of the truth in it. Of who he was.
Shirou gave a small nod, a smile flickering at the corners of his mouth—not one of joy, but of recognition. Of solidarity.
"It's good to meet you, Kurono," he said gently, the way one might greet a wounded comrade rather than a stranger. "You've done well. You've survived this long—and that means more than you know."
Kurono didn't answer. He couldn't. Not yet. His body was standing, but his soul still lagged behind.
"But I need you to stay strong now," Shirou continued, his tone shifting from warmth to resolve, "and follow my lead. There are others… and I can't do this alone."
Kurono finally looked at him properly.
It was a curious thing—though they were the same age, there was a gravity to Kurono's presence that made him seem far older. The experiments, the battles, the horrors—all of them had chiseled something out of him. Something raw and hard. He stood tall, shoulders broad and back straight, the shadows of the laboratory light catching along the lean muscle and tension in his frame.
Shirou, by contrast, was slightly shorter—ten centimetres, perhaps—but there was nothing diminished about him. He held himself with a quiet steadiness, a fire behind the eyes that had seen its own share of pain. Where Kurono looked like a weapon forged by torment, Shirou stood like one crafted by choice.
So even though he had to tilt his head back to meet Kurono's eyes, there was no hesitation in him. No fear. Only that unwavering gaze that cut through the haze like sunlight through storm clouds.
For a moment, the two just stood there—one finding his way back to himself, the other reaching out to pull him through.
And slowly, painfully, Kurono gave a single, stiff nod.
----------------
Kurono nodded slowly, as if awakening from a long and bitter sleep. Then he closed his eyes—and the world around him trembled.
A breath in. A breath out.
From the shadow beneath his feet, something began to rise—not flesh, but something older, something primal. Darkness. Not just the absence of light, but alive and listening.
It answered his will like a loyal hound, surging up and coiling around his arms and legs, not as shackles but as extensions of himself. The lab's pale, clinical light dimmed near him, warped by the presence of that power.
Kurono opened his eyes again, and they were deeper now—more aware, more awake. With a flex of his fingers, he conjured a blade as black as midnight, its edges dancing with flickers of jagged energy. Another motion, and a dozen small orbs of condensed shadow circled him like satellites.
Shirou watched without a word, his heart quickening with both admiration and sorrow. It was a terrible thing, he thought, to be shaped by torment. But it was also the proof of a soul that had not shattered, only hardened.
The blade dissolved and reformed into a shield, then again into thick hooks, shifting with eerie grace. Not summoned, but shaped. The darkness was Kurono's limb, his tool, his weapon—and his only constant companion through his silent war.
"Your control… it's impressive," Shirou said finally, a flicker of a smile tugging at his lips. "Good. Just follow my lead, and we'll make it out."
Kurono glanced at him, and for the first time, there was something human in his gaze. A quiet flame.
But Shirou could tell there were problems still to solve. He could feel it in the odd way Kurono's magic moved—brute force without finesse, raw power shaped by instinct rather than structured spellcraft. The young man had reservoirs of energy, oceans of it, yet no boat to sail across.
"They encoded the language into me," Kurono said, his voice hoarse but steady. "Even the way magic is spoken... they built it in. But I don't know any spells. The translation—it's holding me back."
Shirou's brow furrowed. A clever cage, indeed.
"To master their magic," Kurono continued, "I need to break the spell they placed on my soul. To learn the true language myself."
Shirou gave a single nod. "We'll fix that. One step at a time."
He raised a hand and whispered under his breath. The air shimmered faintly—aegis occulo—and the invisibility spell took hold, folding around both of them like a silken cloak of wind and silence. The world dimmed for Kurono, though not in a way he feared. It was like slipping between heartbeats.
Then, with a flourish of his arm, Shirou summoned Caladbolg, the spiral sword bursting into view with a quiet hum. It hovered in the air beside him, the magical construct holding steady.
Kurono blinked once, surprised to still see Shirou before him.
"You vanished, but then I saw you again."
Shirou grinned. "The trick with invisibility is not to be unseen, but to be seen by the right people."
Kurono nodded, a small smirk tugging at the corners of his mouth. It felt foreign. But it also felt good.
Side by side, one cloaked in white, the other shadowed in black, they began their escape—not just from the laboratory's steel walls, but from the past that had nearly devoured them.
Shirou darted through the winding corridors like a silver whisper, each step calculated, each breath measured. Behind him, Kurono moved like a phantom, swift but silent, his dark cloak brushing the walls with barely a sound.
They kept a careful pace—not too fast, not too slow. Shirou knew how fragile the mind could be after a long stretch in chains. He had seen it before: the desperation to act, to strike, to scream back at the world that had turned cruel. But Kurono was holding it in. His hands clenched and unclenched, the shadows around his fingers twitching with suppressed violence.
A softer man, Shirou thought. Not weak—never that—but someone who had to become hard to survive.
The magical knights they passed wore polished armour and hollow eyes, oblivious to the two fugitives slipping past them. The invisibility spell still held. No counter-charms. No alarms. Either they were arrogant, or simply unprepared.
But then came the final stretch.
Shirou skidded to a halt, eyes narrowing.
At the mouth of a great iron door stood a cluster of magicians, robed and focused, weaving spells like threads in a tapestry. Barriers shimmered like glass domes in the air—layered, reinforced, and humming with power. This was no longer a simple hallway; it was a choke point. A trap meant to stop even the most desperate attempt at escape.
"We're going through," Shirou muttered under his breath, lowering his voice so that only Kurono could hear. "Don't get caught."
He stepped forward, pulling a bow into being with a shimmer of mana and intent. The string gleamed with tension as he raised Caladbolg—a blade not meant for archery—yet perfect for destruction.
He locked onto the mage at the centre. The orchestrator. The keystone.
The air snapped.
A deafening roar split the hallway as the arrow screamed through space, breaking the sound barrier and tearing into the shielded ranks like divine retribution. Light burst. Screams echoed. The barriers shattered like brittle ice.
Shirou didn't pause to admire his work. He was already running, the ruins of magic still falling like stardust around them.
Kurono followed, his coat flaring behind him, the darkness drawn in close as if it too feared what would happen if it were left behind. His eyes were locked forward, not on the enemies, not on the destruction—but on Shirou. The one who had brought him back.
Outside. At last.
The world exploded into green and gold as the forest greeted them—dense trees, wild underbrush, and fresh air that tasted like freedom.
Shirou turned sharply, his eyes sharp with a resolve carved by fire and blade. One last task.
With a wave of his arm, Caladbolg formed again—larger now, glowing with crimson mana that pulsed like a heartbeat. He took aim, not at a person, but at the entire facility. The place that had imprisoned souls and traded in cruelty.
The sword-turned-arrow surged into the sky and fell like a meteor. Fire bloomed.
The ground rumbled beneath their feet as shockwaves tore through steel and stone. Walls collapsed. Towers fell. The sins of the place were consumed by its own ashes.
It was not revenge—it was necessary.
Without waiting for the dust to settle, Shirou grabbed Kurono's arm and vanished into the trees. Leaves scattered in their wake as they vanished into the forest's shadows, heartbeats loud and alive.
They had escaped.