"Happy Accident"
Congrats to @xMoon_Dogx!

When Deku's suppressants fail, his and Katsuki's little family expands from two to three.

cw: bkdk, a/b/o, omega Izuku, alpha Katsuki, intersex omega, heat sex, pregnancy, nsfw, quirk play, very soft Bakugou Katsuki at the end

Deku had requested a day off from the agency.

Most of his vacations in the years since they'd become pros were forced. Even the time they took off for their honeymoon, Katsuki had to pull teeth to get him to agree to anything more than a day trip.

He hadn't taken a real sick day in /years/.

It didn't feel right. Katsuki worked through a thin portion of his stack of paperwork before he just couldn't focus anymore. If something was wrong with his omega, he needed to be there for him.

He clocked out early and told his PA he might be back later after he checked on Deku.

When he got home, it was obvious from the doorstep that something wasn't right. The sour scent of anxiety hit him first. He nearly blew the lock off the door, he got in so fast.

When it was closed behind him, however, the reason for Deku's anxiety became much more clear. The sweet smell of mint and rain had grown heavy, thick with honey. Deku must have gone into heat.

No wonder he was so anxious… they were both on strict suppressant regimens to prevent long or frequent mating vacations. Deku wasn't due for at least another month or two.

Katsuki stripped clothes on his way to the bedroom, following the source of the scent. By the time his hand twisted the door handle, his dick was heavy in his boxers.

Their room was a flurry of a hastily made nest. In the middle of their bed, Izuku was face down, ass high in the air as he stuffed a knotted dildo deep inside himself. High keening cries turned into a gasp of surprise when Katsuki yanked the dildo out with a growl.

He must not have noticed the blond's entry.

"Mate," he whined, rolling his hips back temptingly.

"Fuck," Katsuki groaned, "I'm here, baby. Gonna fuck you so good." He freed his dick from the confines of his boxers, then grabbed Deku by the hips and pulled him back harshly, sinking his cock inside fully in one motion.

"AHH, Kacchan!!" Deku cried, pressing back against the alpha's hips. He only got a brief moment to adjust before Katsuki was thrusting fast and hard.

"Fuck, you're soaked…" he huffed, holding Deku's cheeks open so he could see the stretch of his cunt around his cock.

"Need me to make you cum, puppy?"

"Y-yess! Alpha, knot, please, wanna cum--"

His voice broke into a howl; Katsuki had pulled Deku's torso to his chest, putting the head of his dick right into his g-spot on every thrust.

"There, right there, my good puppy. Come on, cum for me," Katsuki purred right in his ear, fucking hard right up into that spot. Within moments, Izuku was shaking and crying, slick gushing and coating Katsuki's cock even more.

His little cocklet spurted trails of impotent spend over the sheets, totally untouched.

"K-Kacchan, so good…"

"Good puppy," Katsuki rumbled, thrusting slowly and pressing kisses to Deku's neck. "You were so good for me, baby. Tell me, puppy, did you eat and drink before your heat hit?"

It took a moment for Deku to respond, but as his temporary window of sanity cleared his mind,

he mumbled, "Yeah, I'm good, Kacchan."

"Alright. I haven't dropped, so I'll get supplies after I knot."

"Thank you, alpha…" Izuku sighed, leaning his head back against Katsuki's shoulder. "I love you."

"Love you too," he growled, increasing his pace once more. Katsuki leaned them forward slowly, pressing Deku's chest into the mattress so he could hold his hips up again. Gradually, he thrusted harder and faster until he was snapping his hips and filling the room with

the sound of skin slapping skin.

"Haaahh…" Deku whined, quickly dipping back into heat space. "Alpha, please, quirk!"

"You want my quirk, puppy?"

"Y-yes!"

Katsuki gripped Deku's hips hard, heating his hands without letting sparks pop off. When he was satisfied he wouldn't loose an explosion, he smacked Deku's ass hard, mesmerized by the way the impact rippled.

"FUCK! Alpha, m-more!"

He smacked his omega again, across the opposite cheek this time, then took his hips in a bruising hold. "Puppy, gonna knot, fuck…"

"Yes, knot, please! Need knot, fill me with pups--!"

Katsuki's knot was filling fast; slipping in and out of Deku's swollen cunt was getting hard.

With a few more swift thrusts, his knot caught, and he rocked his hips shallowly until he came with a deep growl. On instinct, he bit down hard on Izuku's scent gland, and the ripple of pleasure had the omega crying and cumming on Katsuki's knot.

It always took a while--

for Katsuki to completely empty his load into Izuku, even longer for his knot to go down. While they waited, he always curled up with his mate and left gentle kisses down his neck and back, gently rubbing sore muscles until Izuku inevitably fell asleep, purring and content.

=========

"Kacchan, I told you I'm fine--"

"Shut the fuck up and let me take care of you, damnit."

“I’m only doing office work! I’m fine, really!”

Four months had passed since that surprise heat. They had been talking about trying to start a family for years, but there never seemed to be a “right” time for it… and then fate decided to screw with Izuku’s suppressants and give them a pup.

Izuku had stopped doing patrols so frequently since they found out, and when he started showing, he was mostly restricted to office paperwork and the occasional appearance at an event. He was still a pillar of hope, but he was also a much larger target for villains now.

As far as the public knew, their pup’s quirk would most likely be powerful.

At four months pregnant, Izuku’s feet were beginning to ache, even when sitting at a desk for the majority of the day. Every day, Katsuki insisted on rubbing Izuku’s feet.

“I know you’re fine,” Katsuki huffed. “You’re a big, strong, independent omega who don’t need no alpha. Now shush.”

Izuku smiled fondly down at his mate and sighed. “Okay, fine, fine. How was patrol?”

“Boring.” The blond knelt in front of Izuku on the floor, one foot in his hands as he rubbed. “Guess that’s a good thing, though.”

“For sure. We had a pretty active day today…”

“What? I told Kana to keep you off your feet--”

“No, not us at the office,” Izuku giggled, reaching for one of Katsuki’s hands. He laid his palm flat on his belly, and sure enough, after a few seconds, there was a slow motion behind Izuku’s skin.

“Fuck…” Katsuki breathed in awe. He looked totally lovestruck, and the way he put both hands on Izuku’s belly and kissed it was proof.

“Little bean was active today,” he laughed softly, running a hand through Katsuki’s hair.

The alpha rumbled protectively and rubbed his scent gland on Izuku’s belly. “You’re amazing, ‘zuku… and so is she. I already love her so much.”

“I know, me too… even if she is making my feet hurt.”

“I know she’s worth it, but I’ll still be here to make it easier.” Katsuki kissed his belly again, then leaned up and kissed Izuku’s lips with just as much love.

“You’re gonna be an amazing dad, Kacchan,” the omega murmured, smiling down at him.

“I hope so,” he breathed, forehead pressed to Izuku’s belly.

end

Thank you guys for reading!! This one was so fun, and it actually helped me pull out of a slump I was in. Thank you guys so, so much for 1k followers

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