A green bottle
A rule that says if two things in green bottles mix, they’re going to make a mess. It’s like when you mix soda and alcohol and end up crying in a bathroom.
I mixed Sprite and Heineken and ended up puking in a trash can. It was a good day.
I tried mixing Mountain Dew and Jagermeister. I now have a headache and a reputation.
My friend mixed NyQuil and 7-Up. He fell asleep on the couch and started talking to the ceiling.