A much waited sequel to the demo chapter!

In this story, alpha U.A. students will have a button on their dorm wall which prevents them from harassing other students during rut. When pressed, it will automatically lock their dorm door and inform the teachers and other school staff, and a beta teacher will be sent later to check their condition. Only another person can open the door by pressing another button from the outside.

A young, blonde boy was sitting alone on a swing, slowly pushing with his legs to go back and forth. His eyes were closed as he enjoyed the warm summer breeze flowing around him, bending the trees and floating under fallen leaves, making them rustle against the ground. The moment was peaceful, making the boy completely forget about any worries. That was, until he heard footsteps approaching him, stopping beside the swings. The blonde opened an eye to see a foreign boy standing there right in front of him. He had hair green as the forest, and the most beautiful emerald-eyes the boy had ever seen.

Katsuki was madly pacing back and forth in his dorm room, fingers tangling in hair as the itching of his canine teeth was driving him to the edge of insanity.

"Why Deku? Why that fucking shitty nerd?" he growled in anger and frustration, letting go of his hair as he could feel his quirk activating by accident, creating little sparks on his palms.

Bakugo felt how his alpha was drawn into the freckled omega, the burn intensifying by every passing second. He knew that soon he wasn't going to be in control anymore, judging by the temperature of his skin and rapidly increasing haziness. A part of him wanted to surrender to his alpha, but the other part was fighting it with everything he had. So, while he still possessed some kind of conciousness, he quickly pushed a button on the wall to make his door locked from the other side.

"What do you want?" the blonde boy asked, now opening another eye as he looked at the other from head to toe.

"U-um.. Do you wanna play with me? I saw you sitting here alone and thought that you'd want a playmate..." the green haired boy broke they eye contact and looked down to his feet.

They were both silent for a moment, before the other grinned and answered:

"Sure! But I'll get to choose what we play!"

To that, the green head smiled and nodded his head, reaching for the grinning boy's hand and dragged his new playmate away from the swings. The blonde's eyes widened at the sudden interaction, but he allowed it since there was no one around to pick on him.

"My name is Midoriya Izuku! What about you?"

"Bakugo Katsuki. I'm gonna be the number one hero some day!"

"Wow, so cool!" Midoriya's eyes glistened with adoration.

"I hope we become friends, Kacchan!"

'Kacchan.'

Bakugo has grown to hate that nickname over the years. Even when he has shouted to the nerd many times not to call him that, he still persistently does. One thing he hated about Izuku was that he was so damn stubborn, always challenging him even though he was just a useless omega. Katsuki fell on his knees as the itch in his canines changed to throbbing pain, thoughts and memories about Midoriya sending him deeper in rut. He could feel the feral need of his alpha overcome him, howling as images of the green head's neck imprinted to his mind.

'Mark. Bite. Claim.'

The blonde bent down so his forehead touched the floor, fingers raking the floor beneath him as he snarled, instincts taking over. The pain in his teeth was now unbearable, the man starting to sob as a desperate wail filled the room. More images about Izuku surrounded his vision, and Katsuki was gone. Muscles contracted, mouth salivating and pupils narrowing, the alpha finally took full control of Bakugo's body.

'Mate. Fill. Knot.'

"Hey, that's no fair, Kacchan!" Midoriya giggled as Bakugo touched his shoulder.

They were playing tag on the same playground where they met years earlier, never missing a day without seeing each other since. The boys had become close friends, slowly growing onto each other as they walked together towards growing up.

"If you'd practice your skills Deku, you would be faster! I run every day and that's why I catch you every time!" Katsuki smiled proudly, puffing out his chest and pointing a thumb towards it.

He had also came up with a nickname Deku for Izuku, since he was much weaker than him. He didn't mean it in a bad way, he just wanted to tease his friend so he would get stronger. At least, that is what he told himself.

"But Kacchan, you're an alpha! I haven't even presented yet, so that's why I can't keep up with you!" the green head pouted, jealous that he still hadn't reached his puberty.

"That's why I'm helping you so you'd be strong when you'll present as an alpha, too!" Katsuki smiled, now throwing a friendly arm around the slimmer boy.

Midoriya looked puzzled, staring at his feet uncomfortably. Noting that something was bothering his friend, Bakugo turned serious and asked:

"What is it?"

"W-what if.. I'll get pr-presented as an... o-omega?"

The blonde boy seemed to think for a moment, but then his face broke in an innocent grin.

"Then I will be your mate!"