(In my much younger days I would like to think that I had a better eye than the poor devil in this joke!)

A guy walks into a bar and seats himself next to another guy. They get talking. The first guy has been noticing a really hot girl sitting down the bar. The second guy notices his interest and says he knows her and would he like to be introduced? Of course, the guy is delighted. Introductions are performed and after a while they both depart.

The bartender has been observing all this, of course. He drifts down to the other guy and asks:" How come you set him up with a hot girl that you already know? Why not take her home for yourself?"

The other guy replies: " I don't go for men".