The clouds hung low over Tokyo's edge, heavy with the promise of rain but refusing to fall. The sky above was the color of ash, quiet and oppressive, as if holding its breath for something unseen. Kazuki stood at the edge of an abandoned rooftop, the wind tugging at his jacket, his eyes fixed on the horizon where the city blurred into the hills of Akiruno.
It had been days since their encounter in the underground ruins, and yet the echo of Kaer's voice still lived in his bones. The flame had quieted inside him—but it wasn't gone. It waited. Always.
Behind him, the city's voice murmured faintly—sirens in the distance, a child's laughter from a distant park, the low hum of air transit lanes overhead. Everything felt distant now. Unanchored. Kazuki's hand tightened around the cold railing.
He wasn't alone anymore.
A faint shift in the air behind him was enough—he turned before the footsteps reached him.
Aoi stood there, arms crossed against the chill, her dark hair tied back loosely, strands slipping across her cheek. Her expression was unreadable, but her presence alone stirred something within him—a calm, a tether.
"You said you didn't like heights, " Kazuki said, his voice low.
"I don't, " she replied, stepping closer anyway. "But you keep climbing to places like this when you want to disappear. So I follow. "
A silence passed between them. Not uncomfortable, but full of everything they hadn't said yet.
She looked out over the skyline. "It feels like something's ending. "
"Maybe it is. "
"Or beginning. "
Kazuki glanced at her, his heart thudding softly in his chest. "I never asked for this, Aoi. "
"I know. "
"I wanted to be invisible. Just another student. Someone no one noticed. But now…"
"You still are you, " she interrupted gently. "You're not the monster you fear. "
Kazuki looked down at his hands—one still faintly marked by the black veins that glowed when Kaer's power stirred. He closed them slowly.
"They're hunting again, " he said, changing the subject. "Another class of Hollow emerged in Kanagawa last night. Nightmare class. The hunters couldn't handle it. "
"Are you going? "
He nodded. "I have to. "
Aoi reached out and touched his arm. "Then don't go alone. "
Her words hung there, suspended between them like a fragile bridge. He met her gaze—calm, unwavering, and full of something he thought he'd never deserve.
"I… don't want you to get hurt, " he whispered.
"And I don't want to lose you. So maybe let's stop trying to protect each other by disappearing. "
His throat tightened.
From below, distant shouting echoed faintly—students pouring out of the nearby academy for a break, the energy of life thrumming in the streets. But up here, it was only the two of them, and the quiet truth that neither could run anymore.
Kazuki finally nodded. "Okay. "
She smiled—small, but real.
A sharp tone cracked through the moment—a hunter comms alert. He reached into his jacket and pulled the device from a hidden pocket. The screen glowed with crimson light.
[ALERT: MASSIVE ENERGY SURGE DETECTED – ZONE 9 – CLASS: UNCLASSIFIED]
Zone 9. Near the outskirts. Near the forest.
Aoi read the screen over his shoulder. "That's… where it all started, isn't it? "
Kazuki's jaw clenched. "Yeah. "
And just like that, the wind shifted. A storm was coming.
He turned toward her. "I'll go first. You come in only if it turns bad. "
She raised an eyebrow. "It's already bad. "
"Aoi—"
"You said we stop protecting each other by running. "
Kazuki gave a soft laugh. "You're impossible. "
"Exactly, " she said, already moving toward the stairwell. "So stop wasting time. "
He watched her disappear down the stairs, then turned back to the skyline. His eyes lingered on the shadow of the forest in the distance—darker than it should've been. Something had awakened again. But this time, he wouldn't be alone.
This time, he would finish it.
The ride toward Akiruno was eerily quiet.
Kazuki stood inside the automated train, his reflection flickering faintly against the window. Aoi sat nearby, arms folded, eyes fixed on the distant blur of trees growing closer with each passing second. No one else occupied the carriage. Whether by coincidence or fate, the world seemed to make space for them.
The last time he had passed that forest, it was raining.
Now, the sky remained dry, but heavy with tension, as if remembering the weight of what had been buried there.
"I haven't been back since, " he said, not looking at her.
Aoi turned to him. "Since the runa? "
He nodded.
"It's not just a forest anymore, " she whispered.
"No, " Kazuki murmured. "It's the place where I stopped being… normal. "
She didn't argue. She didn't need to. She had already seen what the power had done to him—how it carved itself into his body, how it moved like a second soul beneath his skin.
The train glided to a silent stop.
Akiruno station was nearly abandoned. The vending machines flickered with tired screens. A rustling wind swept across the platform as they stepped out.
The path toward the forest was overgrown, less familiar than Kazuki remembered. Wild grass clawed at their ankles. Trees loomed closer, the branches creaking like whispers passed between old ghosts.
And then, they saw it.
A rift.
Not a natural one.
The trees bent unnaturally around a central point, where space itself seemed torn open—just barely visible to the human eye, like heat shimmered through broken glass. The air pulsed with static, and a soft hum—low, steady, and wrong—vibrated in their chests.
Kazuki stepped forward, but Aoi caught his wrist.
"You feel that? " she asked.
He nodded slowly. "It's not just Hollow energy. It's… something older. "
Something divine.
The runa, perhaps, was calling again.
But there was no time to speculate.
From within the rift, a sound emerged. Not a roar. Not a growl. But a whisper. A voice, old as the sky.
"Return. "
Kazuki's breath caught.
Aoi's eyes widened. "Did you hear—? "
He didn't answer.
Because in the same instant, something stepped through.
Not a creature. A shape. Covered in layered obsidian plates, humanoid in form but twice as tall, with glowing etchings running like veins across its body. Its face—if it had one—was masked beneath a horned helm, and in its hand, it held a jagged blade that shimmered with unnatural light.
A Hollow?
No.
Something worse.
Kazuki's body reacted before his mind could. He stepped in front of Aoi, his hand raised instinctively.
A flicker of black fire ignited across his palm.
The creature tilted its head.
And then charged.
The air cracked as Kazuki lunged forward, his hand alight with black fire.
The moment their energies collided, a shockwave rippled outward. Trees bent and groaned. Loose leaves spiraled into the sky like dying birds. The creature's sword came down in a brutal arc, striking against the invisible shield Kazuki summoned at the last second.
Sparks. Screams of metal.
And then silence.
Kazuki stumbled back, the veins on his right arm glowing crimson-black, flickering with unstable power. The force of the blow had nearly broken his stance. Whatever this thing was, it wasn't just a Hollow. It moved with purpose. With intelligence.
Aoi tried to pull him back. "We need to run—"
"No, " Kazuki said firmly. "This thing isn't just wandering. It came through that rift looking for me. "
And it was smiling.
He couldn't explain how, but he knew. The creature was enjoying this.
It stepped forward again, slow and deliberate. Every movement oozed control. A warrior's walk.
Then it lifted the sword.
And spoke.
"You carry his scent. "
Kazuki's heart stopped.
"Whose? " he asked.
The creature tilted its head, the voice like gravel rolling through fire. "Kaer. The Betrayer. The Flame That Would Not Die. "
The words struck Kazuki like thunder.
He didn't know this name—at least, not fully. But the runa reacted. His arm flared violently, a pulse so strong it forced him to his knees.
"Back away, " Kazuki growled at Aoi.
She didn't move.
The creature raised its sword high. "Then burn with him. "
Kazuki screamed—not in fear, but as power burst forth from his chest like a volcanic surge. His entire body lit up with dark flame, and the sky above the clearing dimmed unnaturally.
For a moment, the forest forgot it was a forest.
It became a battlefield.
Kazuki met the next attack head-on.
His fist struck the blade mid-swing, and it shattered—only partially, but enough to send the creature reeling. Black energy crackled like lightning around Kazuki's form. One eye had turned completely red, and the right half of his face was shadowed by moving darkness, almost alive.
The creature staggered.
"Impossible, " it hissed. "You've only just awakened…"
Kazuki didn't let it finish.
He leapt—no, vanished—and reappeared above the creature, slamming his foot down with devastating force. The blow cratered the earth, sending the enemy crashing into the dirt, stunned.
He landed next to Aoi, panting, his hands trembling.
She reached out. "Kazuki…"
He looked at her—and for the first time, he realized what she saw.
He wasn't just Kazuki anymore.
He was a weapon.
And whatever Kaer was… it lived inside him now.
The creature dragged itself upright, its eyes burning white.
"This is only the beginning, " it growled. "The Masked King knows you live. And he is coming. "
Then it vanished into black smoke, drawn back into the rift as if snatched by some unseen force.
The rift sealed behind it.
And the forest fell silent.
The darkness of the rift did not welcome us—it swallowed us.
Every step down the fractured spiral of stone felt like an echo of something ancient, something buried far deeper than mere time or memory. The tunnel wound endlessly, no light, no wind, just the low hum of existence pressing against our minds like a second skin. Even the flames dancing along my fingertips—Kaer's mark—felt subdued, restrained by something older than him.
Haruki stayed close behind, his voice low. "It's getting hard to breathe. "
It wasn't just the air. The pressure here was different, as if the space around us was coiled tight with intent—watching, listening. Waiting.
"I don't think this place follows the same rules, " Aoi whispered, her hand brushing against mine, our fingers not quite touching. "It's like we're walking through a memory. "
The word sent a chill through my chest.
Memory.
I felt it again—that flicker of recognition that didn't belong to me. I wasn't alone in my body. I never had been. Kaer's presence stirred faintly, and for a moment, I caught the glint of a battlefield soaked in blood. A throne of ash. A whisper of a promise.
The rift pulsed.
A sudden vibration beneath our feet.
I turned. "Stop. "
We froze.
The walls of the tunnel began to twist—subtle at first, then grotesquely, like muscle convulsing under skin. From those walls came voices. Not clear words, but sound shaped like thought—like regret.
A girl sobbing.
A boy screaming.
My own name, spoken in a voice I hadn't heard since childhood.
I clenched my fists.
It's not real. It's trying to break us.
"Did you hear that? " Haruki's voice cracked. "I swear that was my brother…"
He was pale now, sweat along his temples, but his eyes burned with defiance. He kept walking. So did Aoi. I did too.
It wasn't bravery. It was necessity.
We reached a wide cavern, its ceiling high above us and dripping with translucent veins of crystal. They pulsed slowly, rhythmically, like the breath of some sleeping god. In the center, stone spires jutted from the floor in a jagged circle. Carved into each of them were runes.
Not like the one on my skin. Older. Primitive.
Kaer stirred again. "Do not touch them. "
I froze.
"Don't, " I warned the others. "They're not… safe. "
But we were already too late.
One of the spires cracked.
Then another.
A tremor rolled through the earth as the runes on the pillars began to glow. A deep sound—more felt than heard—shook the chamber, like a scream caught in slow motion.
From beneath the stone, it emerged.
Not a creature.
A wound.
A tear in the very fabric of space.
The rift opened.
Out of it came a presence. Formless at first. Then limbs. Claws. Wings that weren't wings, but blades of shifting blackness. A skull-like mask, cracked and ancient, floated in the center of the mass like a crown.
Class: Nightmare. Subtype: Riftborne.
Its name came to me like instinct—burned into Kaer's memory.
Itsari. The Bound Echo.
It didn't roar.
It spoke.
Not aloud—but directly into our thoughts.
"You bring him here. The shell of war. The broken throne. The boy of ash. "
I staggered back. The others cried out, clutching their heads.
Kaer snarled within me.
"You were supposed to be dead. "
"So were you. "
Itsari moved—not like a living thing, but like a thought made flesh, a wound in reality choosing to walk. With every step, the cavern cracked. Time fractured. My breath came in shudders.
Then it attacked.
A blur. A scream. A storm of void.
I shoved Aoi and Haruki behind me, and the world became fire.
I struck with my arm aflame, a half-formed blade of darkness exploding outward, tearing through one of Itsari's wings—but it simply reformed. This wasn't like the others. It wasn't even alive by our definition. It was the echo of a god's mistake. A piece of a war that never truly ended.
And it wanted me.
I could feel it—pulling at the divine inside me. Feeding on it.
I heard Aoi cry out, saw Haruki try to summon his own power—but this thing was beyond them.
So I let go.
The black flame surged.
My skin cracked—light spilling from beneath. My right eye burned red, my voice layered with Kaer's roar. I launched forward, blade in hand, not shaped by steel but by will.
I met Itsari head-on.
Sparks. Shadows. Heat.
We tore through the cavern.
Every blow felt like a memory lost. Every clash chipped away at my sanity. Kaer screamed in my head—strategy, warnings, rage. But I was drowning in it. In everything.
Then Aoi's voice.
Not loud. Just a whisper.
"Come back. "
I turned—only for a second—but it was enough.
Itsari struck.
The blade pierced my shoulder. I collapsed.
The flames sputtered.
The cavern went still.
Itsari leaned close, mask inches from my face.
"You are not ready. "
It vanished.
Gone.
Not slain. Not defeated. Just… gone.
The cavern groaned as cracks spread above.
Aoi and Haruki ran to me, helping me up. I couldn't speak. I barely breathed.
Aoi placed her hand on my cheek, eyes full of terror and something more.
"You have to tell me everything, " she whispered.
And in that moment, I knew.
She had seen too much.
And I couldn't hide anymore.
The city was on fire.
Not the buildings. Not the roads. But the sky—the very air—glowed with a shimmer of distorted light, as if reality itself was splitting apart. And in that rupture, something ancient stirred.
I stood at the edge of the broken temple—the same ruins I had seen in my dreams, veined with black roots and cracked stone. Around me, the others gathered in silence: Haruki with his fists clenched, Reina biting her lip, Asha resting her hand on the hilt of her weapon, her eyes flickering with barely concealed tension. Even Riven, who rarely showed emotion, seemed disturbed. Only Aoi stood beside me, her presence grounding me in a world that was slowly dissolving into myth.
"You feel it too, don't you? " Aoi's voice trembled, just slightly.
I nodded. "It's like the world's pulse is quickening. "
And it was.
The Rift was bleeding light now, a swirling funnel of flame and shadow twisting above the old stones. And beneath it… something was trying to claw its way through.
"It's him, isn't it? " Haruki asked me. "The thing you saw. The voice in the dark. "
I didn't answer. I couldn't.
Because the voice wasn't in the dark anymore.
It was in me.
—Kazuki…
I clenched my jaw, pushing the whisper down. The god inside me, Kaer, was waking. Not in fragments. Not in dreams. But in full. I could feel the searing heat crawling beneath my skin, the ancient power of war and flame licking my bones from the inside.
But I wasn't ready to let go.
Not yet.
"There's no turning back, " Riven said suddenly. His eyes burned like frozen suns. "Whatever that thing is, it's already broken through the veil. If we don't stop it here, now, this world will collapse into it. "
"Class? " Asha asked sharply, her voice all business now.
"Nightmare-class, " Riven replied. "Possibly above. "
Silence.
Even Haruki stepped back.
I stepped forward.
The Rift flared—like a wound tearing wider.
And then the ground exploded.
A creature burst from the cracked stone, taller than a house, wrapped in a body of molten sinew and jagged blackened bone. Its eyes were pits of writhing red fire. No roar. No screech. Just pressure—the sound of silence crushed into madness.
I leapt, barely avoiding its claw.
Before I landed, the runes along my spine flared.
Kaer… don't—
—Let me burn, Kazuki. Let me fight… let me live.
I hesitated. Just a second.
That was all it took.
The creature's tail slammed into the stone where I had stood. The shockwave threw me back—crashing into a crumbling pillar. My breath left me in a choking gasp.
"Kazuki! " Aoi screamed.
"I'm fine! " I shouted back. Lie. Every bone in my body felt like it had been set on fire.
But I stood.
Because the flame beneath my skin refused to be still.
I could feel the heat crawling higher—coating my ribs, up my chest. The right side of my body was already blackened with Kaer's mark, my eye burning crimson. My right arm trembled. Not from fear.
From power.
Too much of it.
If you keep holding me back, Kaer hissed inside me, you'll die. And they'll die with you.
He was right.
I hated that he was right.
Across the temple, Haruki was flung aside like a ragdoll. Asha tried to charge in, but the beast swatted her away like an insect. Reina barely got her barrier up in time to shield Riven.
It wasn't enough.
They were strong.
But this… this was divine.
I stepped forward again.
"Get back! " I shouted. "All of you! "
"No! " Aoi's voice cut through the chaos. "Don't you dare—! "
"I'm not letting him out, " I said. My voice was low. Focused. "But I will borrow the flame. "
And I let it rise.
The dark fire exploded from beneath my skin, covering half my body in shadowed armor. My right eye burned like a sun. My breath tasted like ash and blood and thunder.
The creature sensed it too.
It turned.
And it hesitated.
Just for a heartbeat.
Now…
I sprinted.
And the world bent around me.
My fist collided with its jaw—not a punch, not a strike, but a volcanic eruption. The monster staggered back, molten shards flying from its face. It roared, furious. Its claws came down.
I dodged. Slid under. Jumped. Slammed my knee into its core. My fingers dug into its side, tearing the bone apart with fire that wasn't mine—but wasn't only Kaer's anymore either.
It was ours.
Me and the god.
And for the first time, we burned in harmony.
The beast shrieked. Its body crumpled.
But then it surged.
With a final roar, it lashed out—claws slashing toward Aoi.
I moved before I thought.
I was in front of her.
The claw hit my back.
I screamed.
My vision went white.
And the flame—
Exploded.
A mushroom of shadow and light ripped through the temple. The creature was vaporized in an instant. Its body melted into nothing.
And then…
Silence.
Ash fell like snow.
I stood in the center of the crater, breathing hard, my body half-charred, the mark of Kaer pulsing across my spine and ribs.
Aoi ran to me.
She didn't speak.
She just hugged me. Tight. Desperate.
And I let her.
For once—I let myself be human again.
But the Rift above didn't vanish.
It just pulsed.
Like a second heartbeat.
Like a warning.
This wasn't the end.
It was only the ignition.
The world fell silent in the moment Kazuki stepped forward.
The twisted realm around him—this fractured, bleeding pocket of dimension carved by the will of a god long dead—shuddered beneath his feet. The air cracked and pulsed with a low, guttural hum, like the heartbeat of a wounded beast buried beneath the skin of the world. Flames lingered in the sky without burning. Shadows moved without light. Time itself felt slower here, as though the universe was holding its breath.
And yet, in the center of it all, Kazuki stood still. His eyes reflected the surreal abyss that surrounded him—a twisted blend of divine agony and mortal memory.
He didn't move because there was nowhere to run.
He didn't speak because there was nothing left to say.
This was it.
The Hollow.
A black sphere floated before him, pulsating slowly like a rotten heart—each beat resonating with raw, ancient power. It wasn't merely a creature. It was an open wound in reality, a gaping hole left by Kaer's death—a thing that had waited, patiently, for the right vessel to come.
It had waited for Kazuki.
Behind him, the others were still recovering. Aoi's voice had called after him earlier, trembling with the kind of fear only love could inspire, but he had walked on without looking back. Haruki had tried to follow, but even he had felt the unseen barrier close behind Kazuki's last step forward.
Now, only Kazuki remained.
The Hollow surged. And Kazuki… welcomed it.
He stepped into the dark.
The instant he crossed the threshold, his body screamed—veins twisting with divine residue, muscles spasming as the power of the god within him reacted violently to the presence of its antithesis. The Hollow was the death of Kaer, the scar he had left behind. To walk into it was to step into his grave.
Kazuki dropped to one knee, clutching his chest as black veins streaked across his skin, crawling upward like vines of ink.
"You are not him. "
"You are not Kaer. "
The voices were everywhere. Echoes of doubt. Whispers of ancient pain. Screams of forgotten gods. Kazuki felt them slither into his mind like worms, unraveling the fragile fabric of his will.
But then… he remembered Aoi.
Her voice. Her touch. Her eyes when she looked at him—not with fear, but with faith.
And he remembered Haruki. Standing in the hallway after the last battle, fists clenched, eyes burning with the fury of a boy who had finally decided to fight alongside the one he could never fully understand.
And he remembered himself. The boy from the valley. The orphan with nothing. The vessel who had chosen to defy fate.
Kazuki stood.
The runes along his arm ignited. The black flame surged through his veins. His right eye bled crimson light as the divine armor began to form—not yet whole, but rising. Each step he took forward was agony. Each breath came with the weight of centuries.
But he kept moving.
Because if he didn't… the world would break.
The Hollow screamed.
It took shape then—no longer a sphere, but a twisted beast of shadow and bone. A massive, sinuous horror with dozens of mouths, all whispering things no human should hear. Its eyes—countless, lidless orbs—focused on Kazuki with hunger.
Class: Nightmare
Subtype: Echo of Ruin
Rank: S (God Residue Entity)
And then, it struck.
Kazuki met the attack head-on. No hesitation. No restraint.
The sword appeared in his hand—not summoned, but born. A warped, blackened blade with veins of red light running through it like molten lava beneath obsidian glass. It was Kaer's will given form—the Blade of Remnant Flame.
Steel met shadow. Light met despair.
The battlefield exploded into chaos.
Every strike Kazuki delivered tore through the creature's mass, but every cut grew back. Every limb severed birthed two more. The Hollow was not a body—it was a concept. A wound. A scar.
He couldn't kill it.
But maybe… he could seal it.
Channeling the last of Kaer's divine energy, Kazuki raised the blade high. His body cracked—literally—bones splitting, skin tearing as the black armor fused completely, encasing him in the form he was always meant to wear.
The final manifestation of Kaer's vessel.
A knight of ruin and flame.
"I am not Kaer, " Kazuki whispered.
"But I carry his will. "
He plunged the sword into the ground.
The world fractured.
A dome of black light expanded outward, swallowing the Hollow. The creature shrieked in pain—real pain—for the first time. The whispers turned to screams. The eyes dissolved. The mouths fell silent.
Kazuki felt the energy drain from him, piece by piece.
But he held on.
He held on… until the world stopped screaming.
And then—
Silence.
When he opened his eyes, he was lying on the floor of the cavern.
The Hollow was gone. The rift sealed.
Aoi knelt beside him, tears in her eyes, her hand pressed gently to his cheek.
"You idiot, " she whispered, her voice breaking. "Don't you ever do that again. "
He tried to speak, but she shook her head.
"I saw everything. I felt everything, " she said, voice trembling. "And I still chose to run toward you. "
Haruki stood just behind her, arms crossed, trying to look annoyed—but failing. His eyes were glassy.
"You're a pain in the ass, Kazuki, " Haruki muttered. "But you're our pain in the ass. "
Kazuki looked up at them both, his heart full and broken at the same time.
He didn't smile.
But his eyes… were finally at peace.