The morning light was thin and pale, filtering through the gauzy curtains of the Kurosawa estate. The air inside the house was still, heavy with the faint scent of brewed tea left over from the night before.
From the outside, nothing seemed unusual. The sprawling three-story home rested at the edge of the city's wealthiest district, its white stone walls and black-tiled roof untouched by the noise and chaos that often plagued the streets beyond its gates. Inside, the quiet was the kind found only in homes that had always been safe — the kind where danger was a concept, not a presence.
That illusion began to fracture before Renji Kurosawa even opened his eyes.
It started as a whisper in his bones — a strange, almost electric vibration that traveled through his arms and legs. Then the pain followed.
Sharp, molten threads seared through his muscles, burrowing deeper with every second. It felt as if something was injected into his veins, threading itself into every fiber of his body. Renji bolted upright in bed, one hand gripping the sheets, the other clutching at his chest as though he could tear the sensation out.
"What—" His voice was hoarse, strangled by the shock.
The world around him blurred, his vision pulsing in time with the pain. He could feel it — something alien pushing into his flesh, threading into his marrow. His heartbeat thudded in his ears, faster, harder. He had no name for it, but in that moment, mana had found him.
And it was rewriting him from the inside.
It lasted only seconds, but it felt like hours. When it finally subsided, Renji was left panting, beads of sweat sliding down his face. His skin tingled, his limbs felt foreign — lighter, stronger, but trembling as if they had been wrung dry.
Before he could make sense of it, a sound cut through the stillness.
A scream.
It came from just beyond his bedroom wall — deep, guttural, and laced with agony. His blood ran cold.
"Ryuuji—"
Renji was out of bed in an instant, bare feet pounding against the polished wood floor. The Kurosawa brothers' rooms sat side by side at the end of the second-floor hall, and the sound had come from his brother's.
He reached the door first.
The handle was warm under his palm, almost feverish. He shoved it open.
And froze.
His brother was on the floor, back arched in pain, hands clawing at the rug as though trying to hold himself together. His dark hair clung to his face in damp strands. The whites of his eyes were darkening, bleeding into black, while his irises burned a deep, unnatural crimson. Veins traced jagged paths under his skin, pulsing faintly with light. His breath came in ragged gasps, teeth clenched hard enough that Renji thought they might break.
"Ryuuji—"
His brother's gaze snapped to him. For a moment — a fleeting, fragile moment — there was clarity there.
"Get out," Ryuuji hissed, his voice raw but commanding. "Block the door… now."
Renji's throat tightened. "No, I can—"
"Now!"
The word was a roar, heavy with something beyond pain — a desperate plea.
Renji's body moved before his mind caught up. He slammed the door shut, the echo ringing through the hall. His hands shook as he turned the key in the lock, the click sounding far too final.
On the other side, Ryuuji's breathing grew harsher, each exhale a guttural snarl. Something — a hand, no longer entirely human — slammed against the door once, twice, before withdrawing.
Renji stood there, chest heaving, palm pressed to the wood between them. He didn't know what had just happened. He didn't know what was happening now.
But he knew one thing.
Whatever had begun in that moment… it wasn't going to end here.
The door clicked shut under Renji's trembling hand, the key turning with a final, metallic snap. He didn't move. He couldn't.
His back slid down the wood until he was sitting on the floor, knees drawn up, forehead resting against them. His pulse thundered in his ears, drowning out everything but the memory of his brother's eyes — those fleeting, human seconds before something else took hold.
"Renji!"
The voice tore him back into the present.
Footsteps pounded down the hall. His stepmother came into view first — her hair unbound from sleep; robe half-pulled around her shoulders. Behind her, his little sister was barefoot in her pajamas, her eyes wide with panic.
"What happened?" his stepmother demanded, already kneeling beside him. Her hands gripped his shoulders, steady but urgent.
Renji opened his mouth, but the words caught in his throat. His voice felt too small for what he had just seen. "…It's Ryuuji. He—"
A sharp gasp cut through his sentence.
They both turned.
His sister had stumbled, one hand clutching at the wall, the other pressed against her stomach. Her legs trembled violently before she collapsed to her knees.
"Runa!" His stepmother darted toward her.
The girl's breath hitched, sharp and shallow, as though something was burrowing under her skin. Her fingers dug into her own arms, nails breaking skin. Her eyes squeezed shut, her teeth clenched against the pain.
Renji didn't need to ask what was happening. He recognized the sensation — the burning, invasive force threading itself through every nerve, every bone.
Mana.
She was awakening.
…
The world changed in silence.
It began with the faintest hum, too low for ears to hear, yet felt in every bone. Invisible threads wove themselves into the air, sinking into every shadow, every breath, every living thing.
Across the city, people stirred in their beds, wincing at pains they could not name. Some gasped as strength they never knew filled their veins. Others clutched their chests, eyes wide in horror as their skin paled, their breath turned ragged, and hunger bloomed where humanity once lived.
The streets woke to chaos.
In one apartment, a woman's scream turned to a snarl mid-breath as her husband stumbled backward, his blood already painting the wall. In another, a child's laughter twisted into a shriek as his body warped, neighbors fleeing down the stairwell only to find the same madness waiting below.
Police sirens wailed, scattering through the streets, their lights flashing like dying stars. Officers tried to pull civilians to safety, only for some to collapse mid-step, convulsing, their hands curling into claws.
The change did not come all at once. For some, it was a slow corruption — seconds to minutes of agony before the mind was swallowed. For others, it was instant, their humanity gone in the space of a heartbeat.
And everywhere, it spread.
Through homes. Through alleys. Through crowds gathered at bus stops, through the quiet corners of temples, through the bright lights of convenience stores.
No one knew what it was.
No one could stop it.
And no one was safe.
Years later, people would call this day the First Wave.