(verb) When friend #1 solicits friend #2 for intercourse or other sexual favors because friend #1 is desperate as shit and has not had any in forever and solicits friend #2 in an inappropriate way, time, or place.
So, I was standing in the bread isle at Giant when Matt approaches me and asks me for "friend-sex"... What the fuck is "friend-sex?!!"
Bob: "Hey, I haven't had sex in a while..."
Bob: "So I was wondering, friend-to-friend..."
Bob: "Just as a favor, could you hook me up with, like, some... friend-sex?"
Jenny: . . .
When two clearly defined friends engage in some form of copulation, while maintaining the same level of friendship.
"Lexi, you're awesome. I think we should have friend-sex."