Chapter 13: Addiction
Kirishima couldn't stop.
He told himself it was just training. Just testing his limits. But every night, he found himself back in Gym Gamma, fists clenched, heart pounding.
Crack. Boom. Snap.
The sound of impact, of destruction, of power, echoed in his ears like a song he couldn't stop listening to.
Tonight was no different.
He stood before a reinforced training dummy, its surface dented from the past few nights of punishment. His breath was steady, controlled. His muscles coiled with anticipation.
This time, he wanted to go further.
He let his body harden, but not all at once. He focused, remembering the sensation, the moment before impact—the way his bones felt heavier, the way the force gathered, waiting.
He threw the punch.
BOOM!
The dummy didn't just dent. It crumpled, snapping off its base and crashing into the wall. The reinforced metal groaned under the force, a deep dent carved into the steel.
Kirishima exhaled, his breath shaky, exhilarated. His skin buzzed with residual energy, a sensation that sent chills down his spine.
More.
He wanted more.
He braced himself and threw another punch, this time against the reinforced training wall.
CRACK!
The shockwave traveled up his arm, through his bones, but it didn't hurt. He absorbed it, felt it flow into him like fuel.
He struck again.
And again.
The wall splintered, small fractures spider-webbing across the surface.
His fist throbbed—not with pain, but with power.
He had been holding back his whole life. Playing defense. Enduring. But that wasn't all he could do, was it?
No.
He was meant to fight back. Meant to hit harder. Meant to break through.
The next day, Kirishima felt different.
He walked through class with an edge, a sharpness in his movements that wasn't there before. He felt the power humming beneath his skin, waiting to be used.
During sparring drills, he moved faster. Hit harder.
When Kaminari threw a punch, Kirishima blocked—not just absorbing the impact, but taking it. He let the energy settle in his bones, storing it.
And when he countered—
THUD!
Kaminari hit the ground hard, breath escaping in a sharp gasp.
Everyone stared.
"Dude," Kaminari wheezed, clutching his chest. "What the hell?"
Kirishima blinked. He hadn't meant to hit that hard.
Had he?
Aizawa's voice rang in his head again.
"The first time you step outside the rules, it's for the right reasons. But every time after that, it gets easier."
He forced a grin, offering Kaminari a hand. "Shit, my bad, bro. Guess I'm just amped up today."
Kaminari took his hand, wincing as he got up. "Yeah, no kidding."
Mina gave Kirishima a look. A deep, knowing look. "You sure you're okay?"
"Yeah," he said, forcing the words out like they weren't eating him alive. "I'm great."
But inside, something twisted.
He wasn't sure if he was lying.
That night, he went back to Gym Gamma.
This time, he didn't just train.
He unleashed.
Punch after punch, he struck, each blow harder than the last. The walls shook. The air cracked with pressure. The dummies weren't just damaged—they were destroyed.
And through it all, he felt something deep in his core.
Satisfaction.
Because this wasn't just strength anymore.
This was dominance.
This was liberation.
The next time he fought, it was against Iida. A training match. Nothing serious.
Until it was.
Iida was fast. Too fast. Kirishima barely had time to react before the engines roared and Iida was on him, slamming into his guard with raw speed and precision.
Kirishima absorbed the impact, let it sink into his bones. It made his muscles coil tighter, his skin hum with energy.
And when he struck back—
He didn't hold back.
As his fist connected with Iida's side, the recoil from the fist sent a blast that reached the edge of the training hall.
CRACK!
The sound echoed like a gunshot as Iida flew across the hall.
His body soon hit the ground, skidding across the mat. He gasped—a raw, choked sound that sent ice through Kirishima's veins.
Silence.
Kirishima's breath hitched. His hands trembled as he took a step forward.
Iida wasn't getting up.