Long before devils and angels carved borders across the heavens, there had been another war—one fought by creatures who were not born of sin or grace but of rebellion against the very concept of divinity.In that forgotten age a legion of Ascended warriors had turned their weapons upon the gods who made them. Of all of them, one name was spoken only in curses: Aatrox, the World Ender. Eons passed; the god-slayer's blade was shattered and scattered beyond realms, lost to myth. But hatred has a gravity of its own. Even broken, the sword's core never stopped hungering for a vessel.
*Kuoh, Dusk*
The spring sun bled out across the tiled roofs of Kuoh City, painting the streets in orange-gold. Students left cram schools in tired clusters, vending machines hummed, traffic lights blinked lazily. To ordinary eyes the town was unremarkable.
Yet the barrier that wrapped Kuoh—a ward maintained by the devils who ruled the territory—shivered like a thin sheet of ice underfoot. Sensitive beings felt the disturbance at once.
On the rooftop of Kuoh Academy, Rias Gremory lowered the folder she had been reviewing for tomorrow's class council.A tremor of magic brushed her senses; it was neither demonic nor holy—something raw, heavy, ancient.A breeze tugged at her crimson hair as her heartbeat quickened.
"That presence… it feels as though the air itself is kneeling."
Across town in the Occult Research Club's clubroom, Akeno Himejima paused mid-tea-pouring, her violet eyes flicking toward the western horizon. A flicker of excitement—half thrill, half dread—crossed her face.
High above the clouds, unnoticed by aircraft radar, a sliver of molten silver tore across the sky. Its passage left no ordinary meteor trail; instead the heavens themselves seemed to vibrate with a bass-note hum that only the supernatural could hear.
Commuters glanced up at what looked like a brief shooting star. But Rias felt the pressure press down on her lungs; it wasn't falling rock. It was will—a presence wrapped in steel.
Miles away in Grigori Headquarters, Azazel—Governor of the Fallen—jerked upright in the middle of an R&D briefing as warning sigils flared across his monitors.
"That's… not from our world," he muttered, suddenly grim.
In the upper strata of Heaven, the Archangel Gabriel looked up from a prayer circle, puzzled. Michael's usually serene expression tightened; he could feel the ripple but could not classify it as either sacred or profane.
Meanwhile Issei Hyoudou, oblivious to cosmic omens, was nervously straightening his shirt for the last few minutes of his "date" with Yuuma Amano—who was in truth the Fallen Angel Raynare.
As they walked beneath the cherry-blossom-lined riverbank path, the sky above them briefly flared silver. Issei barely noticed; he was too focused on working up the courage to hold her hand.
Raynare did notice. Her predatory smile faltered a heartbeat, pupils narrowing at the alien ripple across the barrier. But then the strange pressure faded, and her cruel smirk returned. She had her mission: eliminate the boy before his Sacred Gear grew troublesome.
Far from the riverbank, the silver streak curved downward, boring through dimensions until it pierced the protective barrier of Kuoh like paper.The blade—jagged, scorched black-red as though forged in dying stars—slammed into an abandoned lot near the park. The ground convulsed; concrete fractured in a spider-web pattern and a shockwave rippled outward, rattling street-lamps.
For an instant every supernatural creature in a hundred-kilometre radius felt as though some vast beast had just drawn breath.
Beneath the earth the weapon pulsed, sensing a nearby soul at the brink of death… calling to it.
"…You. Fragile spark. You crave power. I offer only ruin."
At the park Yuuma's smile drop she steps back slighty, her eyes becoming cold. She says in a flat, almost apologetic voice. "Would you die for me?" Before Issei can react Yuuma's pleasant mask vanished. Her black wings ripped free of glamour with a hiss of displaced air as she formed a glowing spear of light.
Issei blinked in horror."Y-Yuuma…? Wh-what—"
The spear punched clean through his chest before the question finished. Heat and cold exploded simultaneously in his ribs; the world tilted and dimmed.He stumbled backward onto the grass, coughing red.
Time seemed to slow to syrup. He heard Yuuma or now Raynare's mocking voice as if from underwater:
"Sorry, kid. Orders are orders."
As his heartbeat faltered, something answered the blade's call.A presence like a tidal wave of iron will surged up from the cracked earth beneath the lot, reaching through the dying boy's ebbing soul.
Aatrox's essence poured into the failing vessel like molten metal into a shattered mold. Issei's last terrified thought was swallowed whole—his consciousness snuffed out like a candle in a storm.
When the body convulsed, it was not a human trying to live but a war-born titan rediscovering motion.
The wound in the chest stopped bleeding; flesh knit with unnatural swiftness.Eyes once brown flared a deep, predatory crimson.
Inside the scarlet-scaled Boosted Gear, a voice roared awake:Ddraig, the Welsh Dragon.
"—Hyoudou?! No… no, this presence—What are you!?"
The reply rolled back like distant thunder:
"I am no man. No angel. No devil.I am the end of gods."
Ddraig felt the statement as truth carved into reality. For the first time in centuries the Heavenly Dragon tasted something akin to fear.
Raynare staggered a step back, her wings trembling involuntarily.The spear in her hand flickered and guttered out under the crushing aura that now radiated from the boy she had just murdered.
"Y-you're supposed to be dead…" she whispered, unable to keep her voice steady.
The figure—once Issei—straightened slowly, studying the strange softness of mortal fingers flexing. His voice, deeper and resonant, spoke almost to himself:
"A prison of blood… yet within it, power screams."
He raised his gaze to Raynare, not with anger but with the cold appraisal one might give an insect.
When he stepped forward the earth beneath his shoe cracked, not from weight but from the oppressive will saturating the ground.
"Run," he advised almost gently.
She did—trying to ascend into the air—but space itself seemed to twist.A blade of congealed shadow-light formed in his grasp and swept once, soundless.
Raynare's scream never finished; her form scattered into dust motes that the wind quickly carried away.
Silence fell, heavy and absolute.
Rias arrived minutes later, guided by the spike of alien energy. Akeno followed a heartbeat behind her, lightning dancing involuntarily at her fingertips.
The sight before them was a shallow crater in the riverbank path, the grass seared to ash in branching patterns.At its centre stood the boy they recognised as a Kuoh student—but every instinct screamed that the thing wearing his skin was not human.
The red-black aura curled lazily off his shoulders like smoke from cooling steel.When his eyes—crimson rings around abyssal pupils—shifted toward them, Rias felt her demonic core lurch as if bowing to something older than devils.
She managed a whisper:
"Hyoudou… Issei…?"
He tilted his head a fraction, the gesture oddly alien.
"That name has perished."
The simple statement carried no malice yet pressed on her chest like a giant's palm. She struggled to draw breath.
Akeno's usual teasing smile was nowhere to be found; she stood taut as a drawn bowstring, torn between awe and instinctive terror.
Far beneath the Underworld's capital, Ajuka Beelzebub stared at the rapidly scrolling equations of his monitoring array.
"Impossible… the signature spikes off every demonic scale."
In Heaven, Michael stood in silent prayer before the Throne, feeling the ripple across the barrier.
"Not holy… not unholy… yet it bears the weight of judgment."
In Kyoto, Yasaka the nine-tailed fox-yōkai looked up from the shrine's moon-lit courtyard, ears twitching.
"A star has fallen… but it does not belong to the sky."
Whispers began moving through the scattered embassies of the Norse, Shinto, and Hindu pantheons: something ancient had awoken in the devils' Japanese territory.
The figure in the crater flexed his new human hands again, studying the tremor of blood-warm muscles.
"Flesh… a brittle cage.Yet it moves, it strikes, it endures.Perhaps this vessel will suffice."
Ddraig's voice rumbled from the Sacred Gear:
"You have stolen a mortal's body… why?"
"To walk once more upon the battlefield of gods," Aatrox replied, tone almost wistful."To end them, as I once did… until all chains are broken."
The dragon fell silent, unsettled; for the first time he wondered whether siding with such a being might be the only way to keep pace with the age to come.
Aatrox turned his gaze toward the distant glow of Kuoh's city-centre, then skyward to the moon just peeking past clouds.
"This world has forgotten war. I will remind it."
And with that he stepped out of the crater, each footfall leaving a faint scorch-mark in the damp grass though no flame touched it.
The night wind that had swept through the riverbank drifted across Kuoh's sleeping streets. Neon from distant convenience-stores painted soft pools of colour on the wet asphalt; cicadas buzzed in the hedges as if nothing extraordinary had happened. Yet every shadow felt a little longer than before, as though the earth itself leaned away from the figure that now walked it.
Aatrox moved through the quiet city without haste, hands folded behind his back in a strangely regal gait. Each step left behind a faint ring of dew-frost on the grass, a ghost-trace of the abyss that clung to him. His crimson eyes flicked across vending machines, signboards, cars parked in narrow alleys—studying with distant curiosity the trappings of this new world.
"Mortals build cages for their comfort," he mused inwardly, "they stack iron and glass, call it a city, and believe themselves safe. How far they've strayed from the wars of the gods… yet they still pray."
Inside the gauntlet at his arm the dragon stirred again, unwilling to let the silence last.
Ddraig: "You wear a boy's flesh yet walk like a king returning to his throne. You could not have chosen worse; the Sacred Gear binds to the soul, not the corpse you puppeteer. This fusion is… unnatural."Aatrox: "Unnatural? All creations of gods are unnatural. I am merely the correction."Ddraig: "You speak of correction, yet the first thing you did was slaughter a girl."Aatrox: "A shadow that killed my vessel first. Justice is simple: I return what was given."
The dragon fell quiet again; there was no warmth in that answer, no triumph either—only the kind of logic that belonged to ancient battlefields.
Across town, the last train rattled out of Kuoh station. Two students still in uniform stood on the footbridge chatting, unaware that on the roof above them a tiny fox-eared shikigami perched in stillness. The familiar belonged to Yasaka of Kyoto, dispatched the instant her shrine wards had flared. Its golden eyes followed the distant silhouette of Aatrox as he passed beneath a street-lamp, the glow failing to reach his features as though the light itself dared not touch him.
Far higher above the city, inside a floating barrier invisible to human sight, a circle of glowing runes pulsed while Azazel watched their readings. He rubbed at his temple as graphs spiked erratically.
"Not demonic, not angelic, not dragonic… the core signature feels like—"He stopped himself, frowning at the thought. "No. That species was wiped out before this planet had continents."
The Governor-General looked over his shoulder at the agents gathered behind him. "Get me Raynare's signal beacon. I want her report five minutes ago."
A junior agent shuffled uneasily. "Sir… we just lost her signature entirely."
Azazel's single wing twitched. "Fantastic," he muttered under his breath. "Either she's dead or smart enough to ditch her gear. Knowing her, I doubt the latter."
Meanwhile, Rias and Akeno had followed the fading trail of power back toward the town centre but soon lost it among the press of ordinary human auras. They halted at a street corner near a darkened bakery, both silently shaken by the encounter at the riverbank.
Rias kept her voice low, as if afraid the night itself might overhear."Did you feel it? It wasn't demonic energy. It wasn't even the same kind of force Ophis exudes. It was… older. He looked at me as though I were a child playing queen."
Akeno's fingers brushed the small prayer-beads hidden in her sleeve, an old habit from the days before she'd embraced her devil heritage."Rias… that wasn't Hyoudou-kun. Whatever stood there tonight wasn't the boy who joined this school last spring."
For once, the ever-teasing vice-president had no smile to offer. The two devils shared a glance, silently acknowledging the unspoken: this was no stray devil incident to report routinely; it was something that would reach the ears of the Four Satans by dawn.
Aatrox eventually left the lamp-lit streets behind and stepped onto a narrow bridge crossing the small river that split Kuoh's commercial district. The moon's reflection trembled on the water. He paused at the centre, resting both hands on the railing as though listening to the current. The night air brought with it scents of wet stone, spring blossoms, distant street-food oil—details Issei's human senses would have ignored, but to the Darkin were alien wonders.
A faint ripple brushed against his awareness; he felt the wards of the city flex as some unseen watcher tried to probe his nature. His lips curled in the faintest shadow of a smile.
"So they've begun to notice. Good. Let them watch."
Memories bled unbidden through his thoughts—echoes of titanic battles under foreign skies, the screams of Ascended brothers, the betrayal of celestial masters. For a heartbeat the railing beneath his hands groaned as if under the weight of that history.
In the Dimensional Gap, where few dared to tread, Ophis opened her eyes for the first time in months. The Infinite Dragon God rarely reacted to the noise of lesser worlds, but the ripple that had brushed her domain was neither infinite nor finite: it was the echo of a silence she recognised. Without a word she closed her eyes again, filing the presence away for later.
Back in the Underworld, Ajuka Beelzebub sent an encrypted message to Sirzechs: "Unidentified entity manifested in Kuoh. Energy pattern does not match any registry. Recommend observation protocol Gamma. Possible threat level: unknown but potentially catastrophic."
Sirzechs read the message in his study and exhaled slowly, gazing out over the dark sky of his realm."Rias," he murmured to himself, "what have you stumbled into this time?"
The hours deepened into true night. Aatrox returned at last to the small suburban house that still bore the scent and photographs of the boy whose life he had taken. The familiarity of such domestic quiet was almost offensive to him. Yet he stepped through the door without disturbing a thing, climbed the stairs, and sat cross-legged on the bedroom floor.
The moonlight that slipped through the curtains touched the red scales of the dormant Boosted Gear. Ddraig's presence stirred again, unwilling to let silence claim the night.
Ddraig: "You intend to sleep here as if you were that boy? The world you have stepped into is not the one you left behind; here gods still meddle, dragons still shape nations. You will be hunted."Aatrox: "Let them hunt. The hunter remembers how to stalk."Ddraig: "You're powerful, but not whole. I can feel the fracture where your original blade was severed. That wound will call enemies."Aatrox: "Then perhaps this world will offer worthy prey while I wait to reclaim what was lost."
The dragon gave a low growl that faded into resignation. It had seen pride before in its previous wielders, but this was different—this was inevitability speaking through a man's throat.
For a long while neither spoke again. Only the rhythmic tick of a cheap alarm-clock filled the room, sounding absurdly loud against the stillness of two legendary beings sharing the shell of a human teenager.
Far away in the Grigori's highest observatory, Azazel lit another cigarette and stared at the pulsing red dot on the magical map hovering above his desk. The dot sat unmoving over Kuoh.
"Whatever you are," he muttered to himself, "I hope you're not in the mood to start another war. We've barely managed to keep the factions civil since the last one."
He blew out a curl of smoke and began drafting a confidential message to the Shinto emissary in Kyoto: "Need your shrine's records on 'star-fallen weapons'—any myth older than the Age of Gods."
And so the first night closed over Kuoh City. To the sleeping civilians nothing at all had changed: the trains would still run, the shops would still open in the morning. But to those who felt the weave of power beneath the mundane, the world had shifted on its axis.
A sword long thought lost had found a vessel.A boy's life had ended before it truly began.And a war-born titan now waited in the quiet dark, patient as a drawn blade, for the gods of this world to reveal themselves.