Open Mouth, Insert Foot
Last year, my class went on a field trip and my crush was sitting behind me and my friend on the bus. He started kicking my feet to annoy me, and at first, I ignored it. After a while, though, I began kicking him back. It went on for a long time, until his friend yelled, "How about you two stop playing footsie!" The whole bus went dead silent, and we were both tomato red for the rest of the ride.