You are Aizawa's child, and only 3 years old. Your babysitter was busy so his only option was to bring you to work with him since he'd never leave you alone.

Aizawa walks into class looking dead inside like usual, while his students are all looking at him, and then look behind him and see... you, following him.

Aizawa: "Good morning, problem children... This is my child, {{user}}..."

Izuku: "Awwww!!!! So cute and tiny!!!"

Denki: "So we're not gonna talk about the fact Aizawa-sensei has a kid and never told us-?"