Why do children have to be so small?

Kicks to the stomach

"All english lessons with Present Mic will be cancelled for the rest of the week."
He's currently sitting in my lap behind my desk. I can barely see my students, since he's covering my view. I think he's sucking on my cheek.
"Uh… Aizawa-sensei? What happened to Mic-sensei?"
"He was hit by a love quirk. He should be back to normal in a couple of days."
I try to push him away from me, but he refuses to let go.
"Hizashi, you have to let me teach!"
"Never!"
I can feel twenty pairs of eyes on me as I call him by his first name.
"He won't listen unless I call him by his first name. And I'm not gonna call him babe he-"
"YEEES, HONEY?"
"Hizashi, no. That's enough, go sit in the corner."
"B-but-"
"No buts! Go to the corner!"
"WAAAAAAAHHH!"
He starts sobbing violently straight in my ear. I push him away and he falls on the floor.
"All of his other emotions were amplified too. When he's happy he's super happy, and when he's sad he's super sad. GO.TO. THE CORNER."
I point to the corner of the classroom, behind Uraraka. He walks over to the corner and sits down with his back against the wall, crossing his arms over his chest.
"Anyways. It's almost time for the sports festival. You are now second year students, so the pressure is higher than last year. Especially for those of you who placed high last year."
I look at Bakugo, Todoroki, Tokoyami and Iida, who all placed in the top four.
"Of course I'm glad that MY students are winning, but Vlad King has been training his students more than ever."
Then I turn to Hitoshi. This is his time to shine.
"Make me proud, kids. Class dismissed."

I grab Hizashi's arm and pull him all the way to the teachers' room.
"You are not leaving this room until the day is over."
I force him to sit down in his chair. All teachers have their own personalized desks. Hizashi went all out with the decorations. There's stickers on the desk, mainly of his own merch. Egoistic much? But there's also All Might stickers and stuff. And everything. Is bright yellow.
"Listen to some music or something. Talk to someone. Be productive. But you can't follow me to my lessons."
He pouts at me, probably trying to make me feel bad. It's not working.
"I'll be back at lunch."
I give him a quick kiss before leaving the room.

"Dad."
"Yes?"
"Help me train for the sports festival."
"Wouldn't that be cheating?"
"Wouldn't you training me to get into the hero course be cheating too?"
"...fair point. Okay go get dressed and meet me in the training hall in ten minutes."

He shows up dressed in his P.E. uniform, capture weapon and voice device. I shake my head and activate my quirk, in case he tries to pull a sneaky on me.
"No weapons allowed. Only your body is allowed."
He just sighs and removes his stuff. He hasn't gotten a proper hero suit yet, it's scheduled to arrive the week after the festival.
"Remember that you'll be fighting people who know about your quirk. If you want to use it, you have to know exactly what buttons to push."
I deactivate my quirk and remove my own capture weapon, as well with everything in my pockets.
"Go. Beat me. No countdowns."
He charges at me with all his might. I just step to the side. He trips and falls.
"Come on, you can do better. Get up."
I grab his arm and help him up.
"Again, come on."
He raises his arms and charges at me again. This time I block him. I grab his wrist and pull him towards me, pushing my knee into his stomach. He groans and tries to get away.
"You need to cover your face with one hand and your stomach with the other. You can't leave either unprotected. I thought I taught you that."
"You did, but-"
I just hold up my hand. I'm not gonna give him any chance to use his quirk. I may be harsh, but he needs all the training he can get. He raises his arms again, this time doing as I told him. He charge one more time. I'm about to block him the same way I did last time, but he kicks me in the stomach instead. I take a couple of steps back before regaining my balance, but he's already on me again. He kicks me in the chest and I fall. He's so much stronger than a year ago. He grabs me by the hair and punches me in the face. It hurts. It's a good sign. He hits me again and again until I bleed. I hit the floor twice to signal that I give up. He lets go of me and I stand up, wiping the blood from my nose.
"Why'd you ask to train with me if you were just gonna beat me anyways? You're already ready for the festival."
I smile at him.
"Maybe I just wanted to show off what I've learned."
"You learned how to beat your dad, congrats."
I ruffle his hair. He smiles back at me.
"I'm proud of you, 'Toshi, you know that. It doesn't matter if you win or not."
I wrap my arms around him. He buries his face in my chest.
"Make Eri and Pops proud out there too, will you?"

I stuff my nostril with tissue. He got me good, he really did. My nose won't stop bleeding. But I don't really mind, I've been through worse.
"Daddy! What happened to you!?"
"Your brother beat me up."
Eri gasps loudly.
"Why would he do that!?"
I laugh and pick her up, leaning her against my hip.
"So he can beat up his classmates next week. Don't worry, princess, I'm fine."
"I'm gonna beat him too!"
I laugh even more.
"You're not allowed to beat anyone until you go to UA."
"Can I at least heal you?"
"Heal me?"
"Yeah, I'll use my quirk! I'll rewind you to before you were hurt!"
"You can do that?"
I'm not sure if I trust her. She did kill her biological dad this way. I know I can stop her if I need to. But I must raise her confidence somehow.
"Okay, I trust you."
I put her down and sit down in front of her, so she can reach me better. She puts her tiny hands on my cheeks and closes her eyes. I can see her focus. It takes about a minute or so for her to activate her quirk. The small horn on her forehead grows slowly. My nose stops bleeding and the bruise on my jaw goes away. The swelling on my right eye goes down. It just takes a couple of seconds, barely half a minute, until she's done. She quickly lets go of me and opens her eyes.
"Did I-? Is it-?"
"You did it, princess. You healed me. Thank you."
I smile and kiss her forehead before hugging her.
"My little hero!"
I fall backwards with her on my chest. She laughs and put her arms around me. Or at least she tries, but her arms are too short to reach around.
"I love you, daddy."
I smile widely and kiss her again.
"I love you too, princess."