A stag fag is a slang term for a woman who either associates mostly or exclusively with heterosexual men, or is best or good friends with a straight man or men. It is a derivative of fag hag
and stag hag
Most of the time, stag fags are homophobes and are usually uncomfortable around other gay men. Like it's phrase-predecessors, it is widely acknowledged that a rich relationship can develop between a straight man and a gay man without sexual tension. The stag fag relationship allows the participants to separate intimacy and sexuality.