Inosuke Hashibira was never the type to question how the world worked.
If it moved, you chased it.
If it fought back, you fought harder.
If it was stronger than you, you screamed in its face until it wasn't.
Simple.
Perfect.
That's why, when he blinked awake on a hot metal rooftop in the middle of a sprawling city filled with towering glass mountains, glowing signs, and strange creatures walking the streets, his first thought wasn't Where am I? but rather—
"What is this, some kind of Demon City?"
It made perfect sense to him. People below had extra arms, tails, and animal heads. One guy was literally a walking rock. Another was a woman with skin glowing like molten fire. That was definitely demon business. He had fought spider demons, drum demons, swamp demons—so why not demon humans?
Inosuke crouched low on the hot rooftop, his palms pressed against the metal. The air smelled strange here—like smoke and hot oil, mixed with something sweet drifting from a street vendor below. But under it all was a different scent.
The scent of prey.
His eyes snapped toward the noise that cut through the city's constant hum—a sharp crash, followed by a woman's scream.
He saw her, half a block away, stumbling backward in an alley as something massive lurched toward her. The "thing" was twice her size, its body warped and bulging in places no human body should bulge. One arm was like a swollen club of muscle, the other stretched unnaturally long with clawed fingers that scraped the pavement. Its skin was patchy, purple and black veins pulsing under the surface.
The crowd gave it space, but nobody rushed in. Some were frozen in fear, others already pulling out their little glowing rectangles to record. The woman was trapped against a brick wall, her voice cracking as she shouted for help.
The villain's voice rumbled through the alley, deep and jagged. "Don't bother screaming, lady. The heroes around here are too slow. You're mine now."
He flexed his clawed arm, the tips scraping sparks from the wall beside her. "I'll make it quick if you stop squirming. Otherwise…" He grinned, showing rows of jagged teeth. "…I like it better when they fight."
To Inosuke, there was no question.
Demon.
His muscles coiled, and his heartbeat thundered in his ears. The city noise faded. Only the demon and its prey existed now.
Inosuke launched himself forward.
One step. Two. Three—then he leapt from the rooftop, clearing the alley's opposite wall with ease. The wind roared in his ears as the ground rushed up, his boar mask's jaws grinning wide.
The demon barely had time to look up before twin flashes of steel appeared in its vision.
Shhhink!
Inosuke's blades, serrated Nichirin steel sharpened to perfection, cut through the monster's arms like slicing through bamboo. Flesh and bone gave way, spraying red blood across the alley walls. The creature's shriek rattled windows.
It staggered, eyes wide with shock, and Inosuke didn't waste the opening. With a wordless roar that echoed between the buildings, he twisted his body mid-air and brought both swords around in a crossing slash aimed at the neck.
Slice!
The demon's head spun away, hitting the ground with a heavy thud and rolling until it smacked into a trash can. The body stood for half a second longer, then crumpled like a puppet with its strings cut.
Silence.
It was the kind of silence that swallowed up everything—the city, the onlookers, even the woman's sobs. For a moment, all anyone could hear was Inosuke's ragged breathing as he crouched over the body, blades dripping, chest heaving.
Then the screaming started.
"What the hell just happened?!" someone yelled.
"Did he just—he—he killed him?!" another voice cried.
"That's not a hero move—heroes don't behead people!"
Phones were up everywhere now, lenses capturing the wild, shirtless man in a boar mask standing over a decapitated corpse.
The woman he'd saved pressed herself against the wall, trembling. "I—oh god—" She didn't finish, eyes darting from the corpse to the masked man.
Inosuke straightened, wiping his blades on the body's shirt. "Hah! That's what you get, demon!" His voice was loud, triumphant. He pointed one blade toward the woman without even turning his head. "You! You're safe now. Go home before more of them show up."
She didn't move, frozen in shock.
"What, you deaf?!" Inosuke barked, then turned his attention back to the demon's head. He picked it up by the hair, turning it in his hands like a trophy. "Not a bad one. Would've been fun if it lasted longer."
That was when the first sirens wailed in the distance.
Blue and red lights painted the alley walls as the sirens drew closer.
Inosuke's head snapped toward the sound, his muscles tightening in anticipation. More demons were coming. Good.
The first one arrived in a blur of swinging motion—a man with a wooden body, his limbs extending and lashing out like living vines.
"Civilians, get back!" the hero barked, his voice deep and authoritative. His eyes locked on the headless corpse, then the blood-slick swords, then the boar mask. "You there! Drop the weapons and—"
Inosuke didn't wait for him to finish.
"WOOD DEMON!" he roared, kicking off the ground so hard the pavement cracked beneath his feet. His blades flashed in the sunlight as he charged, feet barely touching the ground.
Kamui Woods reacted instantly, thick wooden tendrils sprouting from his arms, weaving into a wall between them. "Restrain—!"
"Beast Breathing… Second Fang: Slice!"
Inosuke's arms blurred, serrated blades hacking with wild, unrelenting force. The wooden barrier shredded in seconds, splinters raining down like sharp snow. Kamui widened his eyes, snapping more branches forward to catch him, but Inosuke ducked low, spun, and carved through them in a frenzy, each cut coming from an unpredictable angle.
The crowd gasped at the raw speed—there was no pattern to his strikes, no hesitation, just primal destruction.
"You think your tree arms can stop me?!" Inosuke yelled, teeth bared beneath the mask. "I've cut down demon forests before!"
Kamui Woods gritted his teeth. This isn't just strength—he's fighting like an animal that's learned swordplay. He launched a thicker branch toward Inosuke's midsection, but the boy twisted mid-air, both swords crossing in a savage "X" slash that split it clean in two.
A shadow moved at the edge of the alley.
Eraser Head had arrived, silent as a ghost, scarf coiling in his hands. He narrowed his eyes. If this was a quirk user, disabling it would be the first step. If it wasn't… well, that would be more complicated.
He slipped into position, waiting for the perfect moment. The wild swordsman was too focused on Kamui to notice him—
—or so he thought.
Inosuke's nostrils flared under the mask.
The air shifted. Footsteps, faint but distinct, scraping against gravel. A subtle displacement of wind from above, accompanied by the faint scent of cloth and… something else. Dry, like old rope.
Predator's instincts screamed.
Without even turning his head, Inosuke suddenly lunged sideways, the scarf missing him by inches and snapping around empty air. He landed in a crouch, head whipping toward the newcomer.
"YOU SNEAKY DEMON RAT!"
Eraser Head's eyes narrowed, scarf flicking back into position. "Tch. His reaction time is insane."
Inosuke's muscles flexed as he surged forward, twin swords arcing toward the scarf. Slice it, bind broken, fight won.
The blades hit—
Clang!
Inosuke's arms jolted from the impact. His swords had bitten nothing—no, they had bitten, but the scarf didn't even fray. It moved like living steel.
"What—?" Inosuke grunted, pulling back and slashing again. Sparks flew. No cut.
A growl built in his throat. "Fine. Change of plan."
"Beast Breathing… Fifth Fang: Crazy Cutting!"
Instead of aiming for the scarf, Inosuke exploded forward, zig-zagging between both heroes. His strikes weren't clean or deliberate—they were a blur of savage angles meant to overwhelm and confuse. Each slash was accompanied by a twist of his whole body, blades coming in from high, low, and sideways in an unpredictable storm.
Kamui Woods tried to catch him again, but every vine he sent was hacked apart before it reached its target. Eraser Head's scarf lashed forward, only for Inosuke to dodge at the last moment with a sudden crouch, then spring upward toward the wall. He ran along it sideways for three steps before launching himself at Kamui's flank.
Slash!
Wood splintered from Kamui's shoulder, forcing him to leap back to avoid losing an arm entirely.
"Stop resisting!" Kamui barked, swinging his remaining branches in a wide arc.
"Resist THIS!" Inosuke snarled, flipping over the attack and driving both blades down toward Kamui's head.
The strike didn't land—Eraser Head's scarf finally wrapped around his torso mid-air, halting the downward momentum. Inosuke snarled, twisting violently, but the scarf didn't give an inch.
The crowd was in chaos now—phones filming, voices shouting over one another.
"Is that guy a villain?"
"He's fighting two pros!"
"Holy crap, he's holding his own!"
Inosuke's eyes darted between his two opponents. Tree demon and scarf demon… the scarf's too tough to cut, and the tree keeps regrowing. Need a new angle.
The growl in his throat rose into a wild yell.
"Beast Breathing… Eighth Fang: Explosive Rush!"
He dropped his swords—not as surrender, but to whip his arms forward with such force that the scarf loosened for half a second. It was all he needed. He slipped his torso free, grabbed the scarf itself with both hands, and pulled, yanking Eraser Head forward.
Eraser stumbled a step—and Inosuke headbutted him through the mask, the impact echoing like a drum.
Kamui lunged to intercept, but Inosuke was already scooping up his blades, spinning low to slice through the hero's legs—not deep enough to sever, but enough to make him stumble back with a grunt.
Sirens blared louder now. More heroes were coming. Inosuke's grin widened under the mask.
"Send more demons!" he shouted, chest heaving. "I'll cut them all down!"
Eraser Head wiped a trickle of blood from his lip. "This isn't working. We need backup."
Kamui Woods nodded grimly, vines curling protectively around him. "And fast."
Inosuke crouched low, blades poised, muscles twitching. The fight wasn't over. The hunt had just begun.