Piece of Cake

Sam's birthday is coming up, so Theo and I were discussing cakes. And then the topic turned to the cake for HIS birthday in a few months.

Me: What kind of cake do YOU want, Theo?
Theo: A big trombone!
Me: Ha! That's going to be a little hard for me to make. Do you have a backup idea?
Theo: Um...how about a toilet?
Me (trying very hard not to laugh): I'm not making you a toilet cake.
Theo: Why?
Me: Because it's not appropriate!
Theo: Okay, how about a butt cake, then?

Mmmm, mmmm...who wants a piece of butt cake?