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Izuku focused on the solid weight against his tongue and tried to push past the primal instinct to unblock his airway.
The warning had been steadily growing more insistent the longer he knelt quietly with Katsuki’s cock in his mouth. He wasn’t sure how long it had been since they started. For the first few minutes he’d been able to keep count easily enough; but then, Katsuki nudged the head of his cock against the back of his throat and it had taken all of his concentration not to gag around it.
Gagging wouldn’t have been an instant loss, but it would be a mark against him.
Katsuki had only choked twice when he’d warmed Izuku’s cock the day before, and he’d be damned if he lost on a technicality. It was already embarrassing enough that he’d only managed to hold out for twenty-two minutes before he lost his composure and started fucking Katsuki’s throat like he’d never had his dick sucked before. Anyone would have done the same, for as confident as Izuku was in his own skills, Katsuki was in a league of his own. If he wasn’t sure that he would blow it up immediately, Izuku would get him a trophy— Great Explosion Murder God Dynamight: Number One Cock Sucker.
He hadn’t thought it would be so difficult, keeping himself distracted from how sexy Katsuki looked on the floor in front of him. The real killer had been his nose; the way it had been nestled down against the sensitive skin of his pelvis, where it was impossible to ignore the warm puffs of air. Every time that the slow rhythm of breath broke he knew it was because Katsuki was struggling with him buried as deep as he could go.
Izuku was always surprised at how easy he made it look, to take it all the way down, like his dick wasn’t twice as thick as Katsuki’s. It evened out, mostly, since the blonde’s was notably longer, which was one reason Izuku was having a hard time keeping his own lips flush with the base of it. He knew from experience that if he sucked in and pressed his fingers to the front of his throat he would feel the outline of Katsuki there. It was tempting, there was something about feeling the slick slide inside and the ghost of it externally that drove Izuku wild.
A flood of drool escaped his lips, he’d let them go a little slack as he remembered what it felt like to have that impossibly hot mouth surrounding him. He almost swallowed, almost flicked his tongue up against Katsuki’s cock, almost moaned around it when he focused on the taste of cum that meant he was doing a good job . It was hard to say what was making his own cock fill out and tent his loose shorts faster, the visceral memory of coming undone or the rapidly increasing pulse against the flat of his tongue.
Katsuki, for as hot tempered as he could be, didn’t appear close to snapping a single thread. Izuku blinked away the haze that had settled over his vision and peered up at the calm and collected facade of his boyfriend. He seemed to be scrolling through his phone, thumb swiping up over the face of it but his eyes looked unfocused, staring past the device. The slight twitch at the corner of his mouth, the delicate flush of pink on the high points of his cheeks and the single bead of sweat sliding down his temple gave away how affected Katsuki was. A swell of pride flipped Izuku’s stomach, pleased that he had been able to break even a bit of his concentration, small as it was. It was almost as if Katsuki had slid his fingers into his hair and pulled his head up to whisper ‘good boy’ in his ear.
‘How long has it been? Are we close?’
At this point, he wasn’t worried about losing as much as he was looking forward to sucking Katsuki dry. There was nothing as lovely as the sounds Katsuki made when he was really enjoying himself. Izuku had asked once if he could record it, so that he could listen to it whenever he had to get off on his own, but the scathing look he’d gotten was enough to keep him from asking a second time.
It wasn’t like he was a pervert for wanting a keepsake of his live-in boyfriend of two years moaning and cursing to keep himself from begging. He made the best sounds when Izuku had him belly down, ass up and spread around four of his fingers while he took his time. After years of getting the privilege of being fucked by and fucking Katsuki, porn simply didn’t cut it to get off—he needed to remember every touch, sound, push and pull that they shared.
Before they started, Katsuki had set an alarm with Izuku’s record and the devil on his shoulder was telling him to break as soon as he heard it go off. In a not so direct conflict, the angel on his better side was telling him he’d enjoy it more when Katsuki lost it, even if it took an hour. Maybe this was retaliation for how long he regularly tortured Katsuki on his fingers, if so, he’d take the loss as fitting reparations. Each twitch against his tongue, each tight spasm of his throat, each new gush of saliva slipping down his chin was a push closer to his own edge. If he came in his shorts before Katsuki so much as bucked his hips he’d never hear the end of it. It wouldn’t be the first time that he would have cum untouched with Katsuki, but it would be the first time from simply having his cock in his mouth.
“Deku, you’re making a mess down there.”
Izuku nearly jumped from his skin at the sound of Katsuki’s voice, he hadn’t so much as grunted since they’d started. He didn’t remember looking away from him, but at some point he must have because when he turned his eyes back to Katsuki he looked totally different. His brows were furrowed, pulled to the center in a clear show of concentration instead of relaxed and unbothered. His cheeks that had been dusted pink were fully flushed now and his hair was damp at his temple, those deadly lips that had conquered him yesterday were shiny and parted like an invitation. Izuku, once again reminded of what he’d looked like with a mouth full of cock, didn’t hear Katsuki’s next words.
He blinked up in confusion as he watched Katsuki’s mouth move soundlessly.
With an irritated huff, he dropped his phone on the couch and then slid the pad of his thumb through the mess of drool that was coating Izuku’s chin. When he started rubbing circles of it into his skin, Izuku couldn’t hold back the deep moan from reverberating throughout his throat and around Katsuki’s cock. The chain reaction of strong thighs stiffening on either side of him, a dangerous hand grasping the back of his neck, and the hiss that snakes passed Katsuki’s lips made his own cock throb weakly.
‘How long?’
“Careful, Deku. Good boys don’t cheat, do they?”
Izuku felt another moan threaten, but he closed his eyes and willed it to die before rising. He was rewarded with a gentle pat to a stuffed cheek, the sound of Katsuki’s palm against the spit sticky skin would have been enough to make him blush if his face wasn’t already red. The touch was brief, like they all had been so far, but enough to tease Izuku into hoping that he was about to let go, that he would grab him by the hair and use him like he liked.
‘Maybe even harder.’
Izuku liked to treat Katsuki gently, even when he was fucking into his mouth like a man racing the clock. He never pulled his hair, instead he would pet through the soft spikes or push back his bangs so he could see all of his beautiful face. He didn’t like to choke Katsuki with it, preferring to slow down when he could tell the stubborn man needed a break that he’d never ask for. The look on Katsuki’s face while he fought heatlessly against the tender care that Izuku showed him was more delicious than any strangled tears would be.
But Izuku, Izuku liked to be consumed by Katsuki.
He wanted to feel the stretch of his esophagus, over and over, as it conformed around the length of his pretty cock. He wanted to be taken relentlessly, he wanted to be marked by Katsuki in just the right way—as a show of unchained desire, not simply ownership. Each bite mark, each fingerprint, and each bloom from bruising lips was a souvenir of Katsuki’s love.
Something just for him to fawn over in the mirror for days afterwards.
It was easier to lean into the lightheaded feeling creeping into his consciousness, and to ignore the tears sliding down his already wet cheeks, if he focused on the future. Thinking about what would happen when Katsuki finally snapped was the only thing keeping Izuku from whining around him at this point.
‘It’s gotta be soon.’
He could almost hear the release, the bit back string of curses, no doubt barely contained behind Katsuki’s quickly crumbling facade. Equal parts relief and frustration, probably louder than either of them would be expecting. Katsuki would take his head in both of his hands, cupping his face in a final act of tenderness before firmly gripping green curls and tugging Izuku back until only the flushed tip was left in his mouth.
Katsuki would look down and hold him still, tease him just a little more, and say ‘Deku, such a good boy. Such a slut for my cock, aren’t you, nerd? Never tasted anything this good?’ and then he’d wait, wait for Izuku to try to speak, to answer a slur of ‘Yes,’ before he’d shove back in and hold Izuku tight against him, nose buried in soft blonde curls as he choked.
Then it would happen quickly and without reprieve.
Izuku would try to catch his breath with each drag out of his throat but he’d barely have time for half of one before he was stuffed full again. He’d be free to moan, or at least try to, but it’d be nearly impossible to do more than gurgle as saliva bubbled out around Katsuki and dripped down to his bare legs. The burn of fingers in his hair would distract him just enough from the stretch of his jaw, which was already tired. Katsuki would pour praise down to him like water, a river of ‘take it’ ‘just like that’ ‘don’t look away’ ‘perfect,’ and it would feed Izuku’s ego so that he could keep going.
The sounds that he’d earn from his partner would be delicious, he wouldn’t be able to hold back when he was close to cumming. His breathing would quicken, a gravely moan or pinched off curse would sprinkle in between the slapping sound of heavy balls against Izuku’s wet chin. When he did finally cum, Katsuki wouldn’t do it with Izuku held down tightly. He’d want it to rush into his mouth where he could really taste it. He’d have to hold it there, plugged up with his lips wrapped tightly around the pulsing head of Katsuki’s cock like he didn’t want to let it go. With any luck, he would fill him up until there was no way to hold it all in, some would leak from the seal of his mouth to slide down his chin and join the slick on his thighs.
He’d definitely need a shower.
Once he was done, Katsuki would pull free and twist his fingers until Izuku’s throat was bared to the ceiling. He’d lean down and mouth along the exposed skin, whispering more praise about what a good job Izuku had done, how he waited just like he was supposed to, and that he’d earned every drop. Lips, wet and warm, would travel until he was speaking against ruined freckled cheeks, and then Katsuki would finally tell him he could swallow.
‘Oh no.’
Izuku shifted where he knelt, his own cock had gone from quietly protesting to threatening outright revolt. He could feel the tight strain of his balls between the soft flesh of his inner thighs and tried to squeeze them to keep himself from making a fool of himself.
“Hey, keep still or I’ll have to dock you for it.”
His voice sounded strained, like he wasn’t doing much better than Izuku.
He kept his eyes closed, he couldn’t risk seeing Katsuki’s face again, not when he was a stone's throw away from blowing his own load.
“Fuck, Deku—almost.”
In the background, beyond the growing rush of blood in his ears, Izuku could hear the timer start to count down.
‘Ten’
Izuku held back a whimper, resulting in a tight swallow around the head of Katsuki’s cock that went straight to his own.
‘Seven’
He clenched his hands into fists and tried to focus on the feeling of his short nails biting into his palms instead of the hot coil in his gut.
‘Four’
Katsuki’s thighs against his shoulder were starting to tremble and it made his stomach flip in a familiar way.
‘One’
The blaring sound of Katsuki’s recorded voice screaming ‘DIE!!!’ rang out throughout their living room and in some twisted pavlovian response Izuku couldn’t help the heady groan that ripped through his throat as he came.
He didn’t have room to be embarrassed about it as he shivered through each wave, doing his best to keep his mouth relaxed around Katsuki as he rocked his hips and palmed himself through the wet front of his shorts. It wasn’t until he was fully spent, sweaty and shivering that he realized what had happened. His already burning cheeks were set aflame as he dared to crack open one eye and peek up at Katsuki through wet lashes, fully expecting the smug grin waiting for him.
“Really, Deku?”