Any harsh revenge pranks?

They must be gross/extreme... Maybe embaring, too. I invited her over to my house (we are both girls by the way) and she tied me up, took off my clothes, and tickled me. It was awful... I need something really good. She is not ticklish like me, so I need something gross or extreme. I want some way to torture her. Make them as embaring, harsh or nasty as you can!