Eating cake
When you're licking someone's butt. It's like a fancy word for something gross that most people do in the privacy of their own homes.
My friend eats cake every time we go to the mall. He says it's a tradition.
I saw my uncle eating cake in the grocery store. He looked like he was in pain.
My mom caught me eating cake in the kitchen. She said, 'You're going to get a rash from all that licking.'