When Izuku entered the common area, his usually beautiful emerald eyes looked swollen. Everyone could tell the omega had cried and the sight was breaking their heart.

"We're really sorry, Midoriya..." Kirishima apologised in a small, guilty voice. "We tried to stop him but he smelt your pheromones." Kaminari said, his expression filled with regrets and culpability. If only they had managed to protect Izuku from Aizawa better...

"It's okay, it's not your fault." Izuku assured in a whisper. He was the only one to blame for this situation. After all, he was the one who had tried to hide his second gender and then gone into heat in the middle of gym gamma. No-one else was responsible for what was happening but him.

"Thank you for everything you've done for me, until then." He honestly thanked all of his friends. Even if he had gotten caught in the end, they had kept his secret and helped him during so many occasions. Izuku couldn't be more grateful to them.

"Don't speak as if it's the last time you'll see us, I'm sure everything will be fine..." Ochako's voice trembled as tears welled up inside her eyes. She was trying not to cry but it was so hard. Everyone was refusing to believe Izuku was going to be expelled. It just couldn't be.

"I hope so." Izuku smiled even so there was a lump inside his throat. He had to stay strong in front of his classmates. He couldn't break down now.

"Let's go." A large hand was placed on the small of his back and Izuku looked up to gaze into Katsuki's crimson eyes. No words were needed for them to communicate together. Katsuki had promised things were going to work out and Izuku trusted his alpha.

"Good luck." Todoroki honestly told them just before they left.

The walk to the principal's office felt like forever. Izuku was so anxious that the only thing that was keeping him going was Katsuki's hand in his. The fact he wasn't alone but instead with his alpha by his sides was reassuring him. However, it clearly wasn't enough to completely calm down his nerves once they were standing in front of the principal office's door.

"It's gonna be okay, Deku. I promise you." Katsuki assured him once again and so Izuku took a deep breath, before nervously knocking on the door.

"Come in." A voice answered them.

Izuku locked eyes with Katsuki's crimson orbs one last time before entering the office. Inside, he was met with not only Nezu and Aizawa but also All Might, his mentor's presence taking him by surprise.

"Take a seat." Nezu told Izuku and Katsuki. Once they did, he faced Izuku and looked right into the green haired boy's eyes. "So, Midoriya. You're an omega."

"Yes..." Izuku reluctantly admitted. There was no point in hiding the truth anymore since there was no way he could explain how he went into heat if he wasn't an omega. He fidgeted with the hem of his shirt as he risked a timid glance in All Might's direction but quickly lowered his eyes once he saw the frown on the hero's face, guilt setting inside him at the fact he had lied to the first person who had ever believed in him.

"How did you hide this during the registration? On your medical records, it's written you're a beta. Did you falsify it?" Nezu inquired and Izuku shook his head in response. "I didn't. I presented as an omega late, that's why all my official papers say I'm a beta."

Everyone took a test determining their second gender in the third year of middle school, but since Izuku had presented as an omega for the first time in the last year of middle school, people still thought he was a beta.

"And you didn't notify anyone about the change of your second gender?" Aizawa asked in a tone that showed just how little pleased he was by what Izuku was saying.

"No..."

"Why?" All Might inquired. He wanted to understand why Izuku had hidden such an important thing, especially to him. Lying about his second gender was a big deal, even more in this kind of situation.

"Because I knew that I wouldn't be accepted in the hero course if you knew I was an omega..." Izuku confessed in a whisper. He knew he shouldn't have done what he had, but it had been the only way to pursue his dream.

"Yes, and that's because an omega can't become a hero." Aizawa stated abruptly.

"What did you just fucking say?!" Katsuki immediately burst out at the words, a deep growl slipping past his bared teeth. But he didn't even have the time to say something else that Aizawa was suddenly shouting in response.

"Do you have any idea how dangerous going into heat in the middle of a gym filled with alphas could have been!!? What if you had gotten raped!? What if alphas had started fighting each other to death to get to you!? You're putting not only yourself but also other people in danger! How did you even think it was okay to go to gym gamma when you knew your heat was close?!!"

Izuku wanted to disappear. Aizawa's words were true and it was making things just so much worse. "I-I didn't know my heat was close..." His voice trembled as he answered, his heart beating incredibly fast inside his chest because of his nerves.

"What do you mean, you didn't know?" Nezu asked with an inquisitive look.

Izuku was about to answer but Katsuki quickly cut him off. "Don't, Deku." Being an omega was already bad enough, so admitting that his heats were unstable was sure to get him expelled. They couldn't know about it.

"Midoriya?" But All Might looked right into Izuku's eyes, expectantly waiting for the omega to talk, and Izuku just couldn't bear hiding something from his mentor again.

"They're unstable. I don't know when they arrive..." He inevitably confessed.

Katsuki let out a groan at the words. Now, the probability of Izuku not getting expelled was almost non-existent.

"Don't you take suppressants?" Nezu asked and Izuku sighed as he shook his head. "They don't work on me." He explained, his answer triggering a grunt out of Aizawa. "Really? How reckless can you be? Why do you take so many risks?"

"Because I really want to be a hero..." Izuku responded in a murmur.

It wasn't his fault if he had been born an omega. Nor if his heats were unstable and if suppressants didn't work on him. He just wanted to save people, nothing more.

"Midoriya." Nezu made sure he had Izuku's attention before starting to talk. "I'm sure you understand that being a hero isn't realisable in these conditions. If you at least had normal heats, we could have worked something out so that you could keep study in UA, but the risk of you going into heat and that things go wrong is too high..."

"What does it fucking mean?" Katsuki growled out menacingly.

"I'm afraid I have to expel you, at least from the hero course." Nezu stated and Izuku's heart suddenly stopped to beat at the words.

"Bulshits! Deku is way more capable of becoming a hero than anyone else here!!" Katsuki completely exploded. "You're telling me you're gonna keep some useless shits like an invisible girl in the hero course and fire Izuku who can beat whoever's ass he wants, just because he's an omega?!!"

"Not just because he's an omega, but because he's an omega who can go into heat at absolutely any time." Nezu answered in a calm manner. "What do you think would happen if he goes into heat in the middle of an important mission? He would be completely defenceless while faced with villains, and therefore would surely be killed." He explained, his words unfortunately telling the truth.

"But that's not all. His arousing pheromones would also affect whoever is next to him. It could distract others heroes and cost them their life as well." He added before looking right at Izuku. "Tell me, Midoriya. Do you want this?"

"No..." Izuku had no other choice but to answer. Risking his own life was one thing, but risking other people's life was another. It was the last thing Izuku wanted. "I don't want to cause anyone harm..."

"Fuck!" Katsuki cursed as he realised there was no solution. Izuku couldn't be a hero as long as his heats were still a problem.

"I know it's hard to accept, but that's how things are." Nezu said in what was supposed to be a soothing voice. Tears were already starting to well inside Izuku's emerald eyes, the omega's whole dream falling apart right in front of him without him being able to do anything to prevent it from happening...

"What if he's marked?" Katsuki suddenly asked.

"What?" His words surprised everyone in the room, especially Izuku who immediately looked at Katsuki in question, his heart starting to race inside his chest at the determined look on his alpha's face.

"I said, what if he's marked?" Katsuki repeated. "His pheromones wouldn't be a problem anymore, and it would also surely regulate his heats."

Once an omega was marked, his pheromones would stop affecting everyone but his mate. Like that, Izuku wouldn't be able to distract other heroes on a mission if he went into heat. Moreover, being marked often had the effect to render an omega's heats stable and regular. It also sometimes made them less frequent.

"That's true, but he's way too young to be marked." All Might made them all notice. Marking was like getting married, and nobody got willingly married in their first year of high school.

"I don't see the problem with being marked at my age." Izuku unexpectedly stated.

"You can't be serious. That's a life time decision, don't take it lightly." Aizawa grunted. Marking was irreversible, there was no going back once it was done. It would bond them for life and prevent Izuku from ever being with someone else than Katsuki. His body would never accept someone other than his alpha anymore.

"I'm not taking this lightly at all. I know how serious being marked is, believe me." Izuku replied. After all, he had already thought about it. He had even made researches to know exactly what it was about...

"But I already know with who I want to be for the rest of my life, and that will never change."

Katsuki couldn't help but to smirk at Izuku's confession. He expected nothing else from his omega. "You heard him." He told the teachers in a smug tone.

"Are you serious, Midoriya?" All Might asked again. He was worried Izuku was only taking this decision so that he wouldn't be expelled from the hero course.

But it wasn't the case. Unstable heats or not, Katsuki would have marked Izuku sooner or later. They already knew it could never be someone other than them, after all. "Yes. I am." Izuku answered in a voice that showed just how serious he was. Actually, there was nothing he wanted more than to be marked by Katsuki.

The look inside his emerald eyes was enough to convince everyone about his feelings. Anyone could tell how deep his love and devotion was for Katsuki with just one look at his face.

"So, is the problem fucking solved already?" Katsuki asked and Nezu could only smile in response.

"If it works, I think it is."

I hope you enjoyed this chapter!