We all know what a wing-man is. What we got here is a new twist on the concept, or at the least a subjectively clever name for said concept. This here is when your boy wants to hook up with some chick but for whatever mis/preconception he aint getting his shot. Here is where you step in. You grab her girls number. Then, when you call you invite her out and say "hey, why don't you bring *amy*." This serves two purposes, first and least important is her security blanket of her girl being there. More importantly, you're giving your boy his shot. The rest should be self-explanatory.