The girls'-night-out scenario would be a nasty routine for a fellow to be stuck in. Maybe next time they'll find a group of four or five guys and insist that their 'cock-crazy girlfriend' would love to suck them all off, one after the other. "If you boys don't believe it, just try her. She'll thank you afterwards."
Yes, "just one of the girls" is always an interesting scenario. I do have to be a bit careful about consent, though.