One night, my girl friend and her sister were driving to a cocktail lounge. As they parked, my friend quickly put on some chapstick before going in.

While sitting at the bar, my friend’s sister notices that it wasn’t chapstick that was put on, instead she was looking at my friend with a big red lipstick-clown-mouth.

She did not tell her.

What would you do?

(Yes, my friend slugged her sister really hard when she found out.)