The underpass was empty and smelled like wet concrete and piss.
Izuku's legs burned with every step. Pull day had wrecked his back and his traps felt like someone had been using them as a punching bag. The walk home was the kind of suffering that would've been poetic if he wasn't too tired to appreciate it.
Headphones on. Low-fi phonk bleeding into his ears. He was mentally calculating how many eggs he needed to eat tonight (the answer was "more than seems reasonable") when the sewer grate exploded.
Green sludge erupted from the ground like someone had turned on a fire hydrant filled with snot.
It moved fast.
Way too fast.
The mass hit his torso and wrapped around him before he could react. Cold. Wet. Suffocating. The consistency of gelatin that hated him personally.
"Finally! A body! A meat suit to hide in!"
'Oh, you've gotta be kidding me.'
He recognized this. The Sludge Villain. The one from the first episode. The one All Might was supposed to catch in a bottle. The one that was supposed to grab Bakugou, not him.
'Guess my existence already broke the timeline. Great. Love that for me.'
The sludge tightened around his ribs. Squeezed. He felt the slime pushing toward his mouth, trying to force its way in.
A normal person would've panicked.
Izuku closed his eyes.
The cold woke up.
It had been sitting in his chest for weeks. Patient. Growing. Fed by the constant grind of training, the slow accumulation of a body that could handle more weight, more strain, more of everything he was building toward. The mana pool had deepened every day, and every day the ocean behind his sternum had gotten a little bigger and a little hungrier.
'Let's see if this body can handle it now.'
The sludge forced into his mouth.
He smiled around it.
His eyes opened. Electric blue.
The temperature in the underpass dropped so fast the moisture in the air turned to fog.
The Sludge Villain felt it. The slime around Izuku's chest hardened slightly, involuntary, the way flesh contracts when it touches something too cold.
"W-what—"
Izuku reached into the mana. Not for a corpse. There wasn't one here. But over the last six weeks, lying awake at 2 AM with the cold pulsing under his ribs, he'd figured something out. The power wanted to make soldiers. That was its nature. Its purpose. Feed it a corpse and it would extract a shadow, easy, like pouring water into a mold.
But if there was no mold, you could shape the water yourself.
It just cost more. A lot more. And the result was rougher, weaker, held together by will instead of the blueprint a dead thing provided.
He didn't care. He needed something with teeth and he needed it now.
He shaped the mana the way you'd shape a fist. Four legs. A jaw. Eyes. A body built from cold and pressure and hunger.
"Arise."
The shadow peeled off the ground behind him like smoke given weight. Shapeless for half a second, then solidifying into something with a skeletal frame and eyes that burned pale violet.
The Shadow Hound.
Big. Mastiff-sized. Its body was shifting black smoke held together by necrotic mana that crackled and hissed like dry ice. No fur. No skin. Just shadow and bone and a hunger that was entirely its own.
The air stank of ozone.
The Sludge Villain screamed.
The Hound didn't bark. Didn't growl. It just moved.
One second it was behind Izuku. The next it was inside the slime, ripping through it like a blender through jello. Everywhere it touched, the sludge froze solid. Brittle. Black. Crystalline. The necrotic cold spread through the villain's body like frost across a window, flash-freezing him from the inside out.
The screams turned into wet, choking gurgles.
Then silence.
The villain collapsed into a heap of frozen, shattered chunks.
Izuku stood in the middle of the underpass, slime dripping off his jacket, breathing hard. His chest ached. The mana cost had been brutal. Shaping the Hound from raw power instead of extracting it from a corpse was like trying to sculpt concrete with your bare hands while someone drained your blood.
But it worked.
'Holy shit, it worked.'
The Hound turned toward him. Violet eyes. Patient. Waiting.
He felt the drain immediately. A constant pull behind his sternum, like the creature was plugged into him and drawing power just by existing. A tax on every breath.
'So that's the deal. You stay, I pay.'
He looked at it for a long moment.
"Dismissed."
The Hound dissolved into black smoke and sank into his shadow. The temperature started climbing back to normal.
The drain didn't stop.
It got lighter. Background noise instead of a drain. But it was there. Constant. Like carrying a backpack he could never take off.
'You're still in there, aren't you.'
No answer. But he could feel it coiled under his feet, stored in his shadow like a loaded gun in a desk drawer.
'Awesome. I have a pet shadow dog that lives inside me and charges rent. This is fine.'
He wiped slime off his face and started walking.
***
All Might landed in the underpass thirty seconds later.
"I AM HERE—"
He stopped.
The villain was already down. Frozen solid in black ice that was evaporating into mist even as he watched.
All Might crouched. His massive hand hovered over the remains. The ice was cold in a way that had nothing to do with temperature. It smelled like ozone. Like the air after a lightning strike, but wrong. Older. Emptier.
He scanned the underpass. No heroes. No civilians. No witnesses.
Just frost and silence and the fading scent of something that didn't belong in this world.
"What on earth...?"
He bottled what was left of the villain and stood, staring down the tunnel with narrowed eyes.
Someone had been here.
Someone strong.
***
Three blocks away, Izuku turned the corner toward his apartment.
His phone buzzed. News alert.
"Symbol of Peace All Might Captures Sludge Villain in Daring Rescue!"
He snorted. 'Sure. Let's go with that.'
But All Might had been less than a minute behind him. Which meant he'd been close. Really close. Close enough to have seen something if he'd arrived thirty seconds earlier.
'Did he see me?'
He looked over his shoulder. Empty street. Nothing.
Under his feet, the Hound's cold hummed like a second heartbeat.
If All Might came looking, he'd have questions.
Izuku didn't have answers. Not yet.
He turned up the volume on his headphones and kept walking.
TO BE CONTINUED