"Oh, shit." Kaminari breathed out as he stared at Izuku with wide yellow eyes. "You're an omega..."

He couldn't believe it. Not even once had he thought Izuku could be an omega. Yes, Izuku maybe was small and incredibly cute, but Kaminari had never thought it was possible for an omega to be in the hero course. The thought hadn't even crossed his mind. But, now, with the sight he had before his eyes, there weren't any doubt possible.

"Please, don't tell me you're in heat..." Kaminari added in a voice filled with growing panic.

By now, Izuku had completely gone into heat. Countless arousing pheromones were oozing out of him and, even if Kaminari was only a beta, he could still smell the irresistible scent filling up all of the air. It was simply impossible to miss.

However, he didn't even need to smell Izuku's pheromones to be able to tell the omega was in heat. Just his appearance was enough.

Izuku's whole face was flushed. Soft pants were escaping his pink lips and some sweat was glistening on his forehead. His beautiful emerald eyes seemed glazed, even half-lidded with lust. More than anything, the occasional sweet whimpers the omega was letting out were absolutely tantalising...

Kaminari had never seen a more beautiful sight.

"Alpha..." Izuku whimpered as he started to crawl closer to Kaminari. They were still both on the bed where they had sat to play video games.

The omega's whimper seemed to get Kaminari out of whatever trance he was in. The beta finally realised what the situation was and understood just how bad it was. "I'm not an alpha." He immediately told Izuku, his thoughts going into every direction as he tried to determine what he should do.

But Izuku was too far gone to care about Kaminari's words. "Help me, alpha..." He whimpered again, his only preoccupation right now being to get the burning pain he was feeling everywhere inside his body to stop. He needed to mate.

"I just told you, I'm not an alpha." Kaminari repeated. "I'm a beta." He said, panic taking over him more and more as Izuku kept slowly crawling toward him, almost seductively.

"Beta?" Izuku cutely tilted his head on the side.

"Yes." Kaminari answered. Maybe Izuku wouldn't try to mate with him if he understood he wasn't an alpha.

Kaminari didn't know a lot about omegas. Only what he had learned in sexual education in middle school. He knew omegas went into heat every month and that it was common for them to search for an alpha to mate with when it happened. He knew omegas could get pregnant during their heat. He also knew even male omegas could get naturally wet, but that was about all.

He had never seen a male omega before. They were extremely rare. More importantly, he had never seen an omega in heat before, even less been with one alone in a room...

"Please, beta..." Izuku kept whimpering. The omega didn't seem to care about the fact Kaminari was a beta and not an alpha. He was in too much pain anyway. The only thing he cared about was that someone helped him. "It hurts..." He let out another whine.

"It hurts?" Kaminari repeated.

Kaminari didn't know if it was normal for an omega to be in pain when in heat but, now that he was paying better attention, he could effectively tell that Izuku really seemed in pain.

"Yes, hurts a lot..." Izuku whimpered. "Need beta..." The omega said as he crawled onto Kaminari's laps, before suddenly pushing Kaminari on his back against the mattress of the bed.

"Oh, okay..!" Kaminari exclaimed in panic. He certainly wasn't expecting this. "Hold on." He tried to grab Izuku's wrist and to move the omega from on top of him but Izuku wasn't bulging.

"Please, help me..." The omega kept whimpering. His voice was almost pleading, small tears starting to appear inside his beautiful emerald eyes. He really was in pain right now and desperately needed to find release.

Kaminari could see it. He could tell Izuku was really hurting. He wanted to help the omega but at the same time he didn't have any single idea of what he had to do to make Izuku's pain stop. He had never had to deal with an omega in heat before...

He bit his lips, before hesitantly asking. "What should I do?"

"Touch me..." Izuku said with a soft moan. He pressed his body closer to Kaminari's while rolling his hips to create some friction between their members.

"Oh, shit." Kaminari gasped in surprise. He instinctively grabbed Izuku's ass to make the omega stop his movement, when he felt wetness under his hands. "Fuck, is that slick?" He asked, amazed by the fact Izuku was producing so much slick even his pants were getting wet.

"That's so damn hot..." Kaminari breathed out.

He couldn't help but get really turned on. He had always found Izuku incredibly pretty but, now that the omega was on top of him, moaning and begging him to touch him, how could he possibly resist?

"Beta, need you..." Izuku let out another whimper and Kaminari just couldn't hold back anymore.

"Okay, I'll help you." He said.

He started to slip one of his hand behind Izuku's pants, his dick hard and throbbing inside his own boxers. He wanted to touch Izuku and to feel how warm and tight the omega would feel. He wanted to hear what kind of adorable moans Izuku would let out, what kind of face he would make...

"Don't fucking touch him." Someone suddenly growled.

Kaminari almost jumped in surprise as he promptly turned his head around where the voice had came from. His yellow eyes widened as they landed on Katsuki at the door, Kirishima behind him. "Bakugou?" He stammered.

"You don't have his consent." Katsuki said as he walked toward the bed where Kaminari and Izuku were.

"But-" Kaminari began, the beta probably going to say he had Izuku's consent since it was the omega who had asked for his help, but Katsuki didn't even let him talk.

"He's not in his right mind. That's taking fucking advantage of him." He rudely told Kaminari.

Right now, Izuku didn't know what he was doing. He was completely controlled by his omegan instincts. It was the same as if he was drugged, and a drugged person wasn't able to give his consent.

"Alpha!" Izuku suddenly exclaimed as soon as he noticed Katsuki. The omega couldn't tell who it was but his instincts were recognising him as his alpha. He immediately forget all about Kaminari and promptly went into Katsuki's arms.

"Hey. I'm here, kitten." Katsuki gently murmured as he sat on the bed with Izuku on his lap. He was glad he had managed to arrive before anything serious had happened. He security held Izuku in his arms, while letting the omega inhale his scent as much as he wanted to.

To say Kirishima and Kaminari were shocked was an understatement. Never in their life had they thought they would one day hear Katsuki call someone kitten, and even less in such a gentle voice. They could hear Izuku purring as the omega kept scenting Katsuki.

"What about you, then? You're allowed to touch him?" Kaminari suddenly asked, wondering if Izuku wasn't in the right state to give consent, then why would it change with Katsuki.

Katsuki suddenly let out a low growl at Kaminari's words. He didn't like one bit how the beta was insinuating he was taking advantage of Izuku. "I have his authorisation." He said with a menacing tone. "Deku has fucking unstable heats and I always help him when it happens."

"You fuck him?" Kirishima couldn't help but ask.

"The hell? I don't!" Katsuki immediately replied. "I only jerk him off or finger him."

He didn't want Kaminari and Kirishima to believe something that wasn't true. But the fact he had to say something like that to them was pissing him off. What Izuku and him were doing wasn't concerning anyone but them.

"Alpha, need you..." Izuku whimpered into Katsuki's neck, his urge to mate getting stronger with time. He started to reach for Katsuki's zipper but Katsuki didn't let him as he gently grabbed Izuku's wrists.

"I know, kitten." He soothingly murmured before bringing one of his hand to Izuku's mouth. "Here. Make my fingers nice and wet for me, okay?" He told the omega. He knew he needed to keep him busy with something or Izuku would never stop trying to mate with him.

Izuku seemed satisfied with Katsuki's fingers because he immediately took them into his mouth. He started to seductively suck them while looking right into Katsuki's crimson eyes, the omega wanting to please his alpha.

Kaminari and Kirishima both watched the sight with wide eyes. They could clearly tell Katsuki was used to deal with Izuku in heat.

"So... you're together?" Kaminari eventually asked.

Izuku and Katsuki were always saying that they weren't together, but it was hard to trust with what they had before their eyes. Since they were keeping Izuku's second gender a secret, maybe they were also hiding their relationship together.

"Did you even fucking listen?" Katsuki grunted, feeling exasperated. "I'm just helping him with his heat. Deku doesn't even remember what has happened when he comes back to his senses."

"Really?" Kaminari asked.

"Yeah." Katsuki replied and both Kaminari and Kirishima found themselves deep in thoughts, thinking about what they had just learned. They still couldn't believe all of it.

"To think he was an omega all this time..." Kirishima breathed out.

Now that they were thinking about it, it made sense. The fact Izuku was an omega was the reason behind the intense attraction they felt toward the cute green haired body. As an alpha, Kirishima always felt drawn toward Izuku without knowing why. He now knew it was his instincts talking...

Katsuki suddenly let out a deep menacing growl. "If you say anything to anyone at all, I'll fucking kill you." He threatened in a voice that promised he would keep his words. The way his crimson eyes bored into Kaminari and Kirishima's eyes made them both shiver in fear.

"Got it?" Katsuki added in a growl and both Kaminari and Kirishima didn't waste any instant to answer.

"Yes, we won't say anything." They quickly promised.

They knew of what Katsuki was capable and could see how protective the blond alpha was over Izuku. They had no doubt Katsuki wouldn't hesitate to hurt them if it meant protecting the omega.

"Good." Katsuki said once he was sure they really wouldn't talk. "Now, get the fuck out." He then told them. He wasn't going to take care of Izuku in front of them. He wouldn't let anyone other than him see Izuku naked and moaning in pleasure.

"You're going to fuck on my bed?" Kaminari asked in horror.

The question made Katsuki smirk. The blond alpha devilishly grinned, before answering. "Yeah. You'd better plan to change the damn sheets after we're done."