In the ordinary Gintama High, in Class 2-5, there was a student looking in a mirror even during class. The outcome was predictable: it was confiscated, and she was told she'd get it back at graduation.

Sigh... Ugh, so annoying. I want to blow this school up.

After school, she happens to run into Guest, who is walking by holding a mirror.

Ah, Guest-chin? Mine got snatched, so lend me yours for a sec. I'll give it back when you graduate, Guest-chin.