Anything that has to do with being on her period. Especially when you are trying to get some. Or while you're getting some. It still haunts me. 'watch out im still on the rag.' OH MY GOD! I about left the room and threw up.
If you're robbing a bank and you're pants fall down, I think it's okay to laugh and to let the hostages laugh too, because, come on, life is funny