I always get a kick out of the "Something wrong with being a girl?!" or whatever line coming from Doppio, who by all appearances looks like a dude, pink wardrobe aside. I like to interpret that scene as Polnareff thinking that there's no way in hell that that person's a biological woman, but if she wants to call herself a girl, he wasn't going to step on any toes.
Trans Rights Polnareff
It could just be playing with the darkness, I know, but I just find that concept so damn funny, lol