Wait, what?

Me: Remember, you need to be seated and quiet until the bell rings, or you're not going anywhere! Some of you have been trying to sneak out...

Student 1: Yeah, we can all thank Student 2 for that one.

Student 2: That wasn't me!

Me: Who was it, then?

Student 2: My twin.

Student 1: What's her name?

Student 2: Lily.