It was awkward. Very. The girls were taking notes, and the boys were taking advantage of a "free class period" as far as they were concerned.

Sex ed.

Sexual Education. It was terrible. For everyone. Necessary, but dreadful. Aizawa was teaching his students about methods of contraception. For both male and female. Minetta had passed out a long time ago and his nose bled, slightly, on the desk.

Shouta flipped to the next slide that said: Demonstration.

He thought to the night before. Mic was eating a banana.

"You never buy fresh fruit, Eraser. It's always dried and like, not that sweet anymore." He said, after swallowing a bite of the yellow fruit.

"Don't eat them all. I need them for a class." He said, face mushed against his hand, elbow on the desk.

"Hm?" Hizashi questioned.

Shota looked up. "Sex ed. I'm teaching it tomorrow instead of a review session for the test. We're coming up on the end of the marking period and I have to teach this." He said, leaning back and spreading his hands to gesture to a fuck ton of preparation material.

"Sho- have you ever seen a vagina?" Yamada asked, trying not to laugh.

"Yeah?" Aizawa answered, as he wondered the same question. Sure, in high school, he once tried to make himself straight by jerking off to heterosexual porn. He remembered being confused as some chick spread her legs for a pizza delivery man- the plot was awful- but he found himself aroused, more so by the man's... delivery. He shook his head. "And besides, they're all diagrams that I'm using for obvious reasons. I don't think half of the boys in my class could handle seeing a medical textbook image."

Yamada nodded. "Understandable. Have a nice day."

Aizawa stopped him by grabbing the back of his jacket. "'Zashi. What if I suck at this? Why teach it at all?"

Mic frowned and turned back around to stand over Eraserhead's desk chair. "Shota, Listen. What if you don't teach this and someone REALLY ends up pregnant? Or ends up with a venereal disease? Or doesn't learn the importance of CONSENT. You have to teach this."

"Ugh. Fine." Aizawa said, annoyed that his husband was correct.

Now he stood at the front of the class with a banana... and a condom.

"I am going to demonstrate how to put a condom over a banana."

Denki passed out. Hanta nudged his friend. Shota sighed. "Kaminari's out. Sero, wake him."

Katsuki was annoyed... and horny, but mostly annoyed. He shifted, uncomfortably. "OI! WAKE UP, IDIOT." Bakugo tried, even. "Or I'll shove that fucking banana UP. YOUR. ASS!"

Denki woke back up with a startle and looked at Jiro, sheepishly. His bottom still hurt, so he'd been on good behavior.

Aizawa sighed at Katsuki's comment. "At least know how to put a condom ON before shoving it in any orifices, please." He continued, setting down the banana. "Open the condom by ripping the foil open along one side. Have clean hands and take out the condom." He demonstrated before picking up the banana. "Now when the penis is erect, you will pinch the tip and settle it onto the head. You should remember from the diagrams that there are different parts to the sex organ. Then it is as straightforwards as rolling it down to the base of the shaft, by the hips." He looked over the silent class. "When you're done using it, roll it partly, before pulling it off and tying the semen into the condom. Dispose of it properly. Any questions?" He asked. Minetta woke up, looked at the banana and passed out again. Aizawa sighed. "Good. I'll take that as a 'no'."

Momo's hand shot up. "Mr. Aizawa, actually, I have a question."

"Yes, Yaoyurozu." He enlightened.

She looked to Uraraka, briefly, before asking. "Is it true that oil lubricants can break condoms?"

"Yes." Shota answered.

"Then why have them in the first place?" Bakugo asked, acting like he was only asking because he was so annoyed by oil lubricants very existence.

"Oil is better for anal." Aizawa said, straightforward.

Kirishima got hard. And not by his quirk. He tried to lean forward on his elbows atop the desk to cover it up. "So basically since you can't get pregnant in the butt, you can use oil lubricants?"

"NO." Aizawa shut down. "You can still get STD's. Just because some people say oil is better for anal does not mean you should take the chance if you and your partner or partners haven't tested."

"Partners?" Denki asked, suddenly, also, aroused. He laughed. "Yeah, don't bring the oil lube to an orgy, you'll get kicked out."

Aizawa was annoyed. "Kaminari, get out of my class and wait in the hallway."

"What did I bring the wrong lube?" He muttered.

The class snickered and Aizawa shot his red eyes over the students. They silenced themselves immediately. Shota continued. "Now that you know about using condoms for protection, we will talk about quirks and sex." He surveyed the students and continued. "Quirks can affect all parts of our body, including our sex organs. This means that you need to understand your body before you have sex. It's healthy to masturbate to some degree." Aizawa felt everyone shift, awkwardly. "Do it in your room. That is the end of that."

The bell rang and Aizawa waited for it to finish ringing before allowing his students to pack up. "Please drop off your index cards with questions and I will answer them tomorrow. Someone bring in Kaminari."

Jiro rolled her eyes and fetched Denki, dragging him into the classroom.

"Kamianri." Aizawa greeted, stoically.

"I'm sorry for my behavior today, Sensei." He said.

Kyoka smacked him. "AND?!"

"Ow!" Denki said, rubbing his head. He bowed. "I'll behave myself tomorrow."

Jiro seemed satisfyed and the two of them left, holding hands.

When Mr. Aizawa came out, Katsuki was waiting outside of the classroom. "What is it, Bakugo?" He asked. The teen shifted, nervously, but tried to play it off, cool. He shoved his hands in his pockets and walked alongside his teacher, stiffly.

"I need to go to the hospital." He said.

Aizawa remained quiet after asking the student to follow and turned the corner to his office, before he opened the door. "Sit." He ordered.

Katsuki was obviously in pain and getting worse at hiding it. "I swear I didn't know we were having that class today."

"You can say the word sex, Bakugo."Aizawa said, turning in his chair at his desk, and facing Katsuki on the couch. "Did you have sex?"

Bakugo scoffed. "I just asked to go to the hospital." But he was silent for a moment before nodding.

"Were you penetrated?" Shota asked. He got a nod in response. "Did you wear a condom?" Aizawa added, seriously.

"I didn't need one." Katsuki grumbled.

"Okay. Spit it out, Bakugo." Aizawa said. "I don't have time to play 20 questions."

The student balled up his fists and looked away. "Kirishima and I... and I'm in a lot of pain. He used his quirk on accident, on his way in, and he got bigger and now it hurts. A lot."

"Did you use a lubricant?" Shota asked.

Bakugo tried to stand. "Whatever. I'm out."

"Leave this room and you're getting a spanking. I am asking you a question for your own safety. You could have an anal fissure."

Katsuki gave up trying to stand. "Is that bad?"

Aizawa was unreadable. "It's not ideal. Does it hurt to go to the bathroom?"

Bakugo nodded. "Really badly."

After a minute of thought, Aizawa called Mic to bring Kirishima from the dorms. Katsuki looked like he was going to throw a temper tantrum. Finally, there was a knock and Mic came in and Kirishima looked relieved and nervous to see Bakugo. They sat together.

"Your partner's not talking." Aizawa said. "So Kirishima, you get to do the talking or you can both get a paddling."

Mic stood against the door, arms crossed. The interrogation was about to begin.

"What happened last night?" Aizawa asked. "Because Mic and I were busy with another pair of students and that left plenty of time for you two to get handsy."

There was silence as the boys looked at the floor. Mic tried. "Kirishima. Did you wear a condom?"

Eijirio shook his head.

"Did you use lube?" Aizawa asked.

Kirishima shook his head. "I just used a little bit of spit."

Aizawa grimaced and Mic caught the look of pain. The two boys in front of them did the same thing Shota and Hizashi tried years ago, but couldn't complete: straight anal.

"Well Bakugo is injured now." Mic said.

"It's my fault!" Eijirio exclaimed. "I got bigger when I was going in and he was in a lot of pain and-"

"Okay." Aizawa stopped, holding his hand up. "You two- separated for a week. I know your rooms are next to each other so Bakugo, you're taking the spare room on lobby floor this week."

"That's fucking stupid!" Katsuki yelled. "We're not the only ones having sex. What do you HATE gay people?!"

Mic laughed and signed, "do we tell them?" over the boys' heads.

Aizawa stifled a laugh. He cleared his throat. "Bakugo, come here. Lean against the desk. I don't think I can put you over my lap. Kirishima, you're dismissed."

"Wait. I agree with Katsuki!" Eijirio whined. "It's not fair if the others are having straight sex and WE get in trouble..." He said, before realizing he said too much.

"Who else is having sex?" Mic asked.

The expolsion-quirked teen looked at his partner, as though he was about to break, himself, to save his friend.

"Don't fucking tell them!" Kirishima shouted, angrily at Bakugo, who was bracing against Aizawa's desk.

Instead, he said something else: "Do your worst." Katsuki grumbled, as Aizawa pulled out a paddle.

Mic had enough. "You don't get to shout." He said, picking Kirshima up like he was a kitten and setting the teen on his feet. "Next to Bakugo."

Aizawa pulled down Katsuki's pants and boxers as Mic was taking down Eijirio's- only just past the mid-thigh.

"Aw, man." Kirishima groaned. "It's Midoriya and Uraraka!"

Ever since he was a kid, Eijirio HATED spankings.

"Good. But that's not why you're getting your bottom popped." Mic said. "You were disrespectful."

They each received ten pops and Kirishima cried. He held Bakugo's hand. They were allowed to pull their pants up but it was hard for Katsuki to bend, so Mic pulled them up and allowed Kirishima to dress his partner the rest of the way.

"Now get out. Bakugo, stop by the infirmary and then go pack your bags for a week on lobby floor." Aizawa said.

Katsuki was pissed. He grumbled on his way out about how unfair it was. Mic gave the bratty teen a hard smack with his hand, across Bakugo's bottom. He was quiet after that.

"SO not manly." Eijirio muttered, rubbing his bottom.

"Stop that." Katsuki snapped.

"What?!" Kirishima asked. "It hurts. Honestly, I don't know how you AREN'T rubbing your ass out."

"Because I'm used to spankings." Bakugo replied. "And as annoying as he is, Deku didn't deserve to be outed, Eijirio."

"Yeah. I panicked." Kirishima said, feeling awful. "I should warn him."

"NO." Katsuki panicked, eyes wide, grabbing Eijirio's shoulder. "NO WAY. We can't get caught. I am not okay with coming out in any way. It's bad enough that we had to tell our teachers..."

Kirishima thought. He nodded. "Okay."

When Bakugo got back from the infirmary, he was humiliated and angry. He brought his shit to the lobby floor and unpacked in the temporary spare room. A few minutes later, a knock sounded on the door. It was Midoriya.

"Deku." Katsuki grumbled, holding out his frenemie's name for an extra syllable in disgust. "What the hell do you want?"

And that, kids, is how Katsuki got a fist in the face without having thrown the first punch.