When you share a bed with someone you don't want to have sex with, so you lay on top of the top sheet to prevent contact. When alcohol is involved usually works.
Trucker 1 "Hey Boomer, I'm 10-8 to the Windy City, I fancy slip seating Mrs Boomer, 42?"
Trucker 2 "That's a big 10-4 Admiral Scuttlebutt. I'll be checking out the Junk Buzzard of a lot lizard in Choo-Choo town"