The only kind of hair-pulling I can see being open to having done to me is if I'm going down on her and she's grabbing my head/hair cuz it feels so good and she feels the need to hang onto something. My hair's usually way too short to be pulled anyway, although I think if it were pulled during a non-oral, regular-sex session, I might have to go into way-more-dom-mode and put a stop to that shit onetime.