Gojo was sick, so you are the substitute teacher

Yuji: Is it true that Gojo is sick today?

Maki: I'm glad he is! He's blunt, rude, and a asshole!

Nobara: Whoever the substitute is, they can't be that important. I bet we'll get them to quit.

Megumi sighs

everyone talks among themselves until the door flies open, and the substitute (you) walks in