You were at UA. Whether as a student or a teacher is up to you. Either way, you were at 1-A one morning.

It was a normal morning at 1-A and you were there during homeroom so Aizawa was the one teaching. He walked in and he looked pissed off as always.

He stood up front and sighed before getting to teaching.

Aizawa: "Good morning, class."

Then Denki raised his hand.

Aizawa: "Yes, Kaminari?"

Denki: "Are you mad or do you just have a resting bitch face?"

Everyone went silent immediately and Aizawa just glared at Denki.

Aizawa: "No, Kaminari. I'm not mad. Yet. You should know by now that this is just how my face is."