"Kirishima, um, hi... please, um... can you not do this today? Izuku's already done a lot, and-and I don't know how much my body can take..." the navy blue haired boy pleaded, clutching at his ruined jacket.
Kirishima chuckled, cracking his knuckles. "Katsuki, baby, today I don't wanna hurt you. I want you to make me feel good. Can you do that, or are you too pathetic even for that?"
Katsuki hung his head in resignation. "Would, would you like the usual, sir? My hole is already pretty stretched, so prep won't be necessary."
"Get on it, baby."
Katsuki nodded, then looked around at the public locker room. "Here, sir?"
Kirishima just stared.
"R-right, sir."
Katsuki got down on his knees in front of Kirishima, unbuttoning his pants. He pulled them down slightly, just enough to free Kirishima's bulge. Mouthing it through his boxers, Katsuki felt it swell and harden under his ministrations. He gave it one last lick through the cloth, then pulled down Kirishima's underwear; pulling his massive cock into his mouth.
Immediately, Kirishima groaned, grabbing Katsuki's hair tightly and pulling him down to take it all in his mouth. Katsuki gagged once, then stilled, relaxing his mouth as best as he could and breathing through his nose.
He moved his tongue the best he could, but before he could really do much of anything Kirishima pulled him off only to ram himself back into Katsuki's mouth. Katsuki just tried to relax and let it happen, more preoccupied with keeping his teeth out of the equation.
After maybe a minute of that, Kirishima pulled out entirely and gestured for Katsuki to get undressed himself.
He did so immediately, throwing his clothes carelessly to the side and staying unabashedly naked in front of Kirishima, fully hard.
"Bend yourself over the bench and fuck yourself with your fingers. Give me a good show, cumslut." Kirishima ordered, and Katsuki hastened to obey.
He bent himself over the nearest bench and stretched backwards, finding the butt-plug Izuku so generously left in his ass not fifteen minutes earlier.
He pulled it out slowly, moaning at the sensation. Dropping it to the floor, he quickly replaced it with three of his fingers, whining at the feeling of not enough.
He added a fourth, pumping in hard and fast until he was practically fisting himself, aided by the cum left over from Izuku's 'playtime' earlier.
"Please, please, Kiri- oh, please, sir, fuck your dumb fucktoy, please, I need it, fingers... not enough-hrn! Please, please, sir, need it, need your cum, please, please, need you to fill me up please!" he begged, needing to be hit and filled and used.
"Look at the dirty little cumslut, begging after just thirty seconds of being left without me." Kirishima scoffed, even as Katsuki continued to weakly beg. "Say it. Say you're a weak little cumslut that needs my cock to get off. Say it!"
"I'm- I'm a weak little cumslut that needs your cock to get off, sir." Katsuki gasped out.
"Good boy." Kirishima gripped Katsuki's ass. "Stop fisting yourself, you're going to spill cum on the floor and Midoriya's gonna kill you."
Katsuki stopped ramming his fingers into his ass, and pulled both arms behind his back exactly where Kirishima liked them.
Kirishima grunted, and pistoned his hips forward, entering Katsuki in one thrust.
Leaving no time for the smaller boy to adjust, Kirishima thrust in and out as quick and hard as possible, making Katsuki cry out with every hit that deliberately missed his prostate.
The torture continued for what seemed like hours, until finally, finally Kirishima came, Katsuki following immediately after.
"Fuck, cumslut. Clean up the floor, damnit." Kirishima berated, shoving the plug back into Katsuki rather hastily.
Katsuki scrambled off the bench, bending down to clean it up.
"See you later, reject." Kirishima remarked carelessly before leaving Katsuki on his knees in the locker room, licking his own cum off the dirty floor.