it could be pee - especially if your girlfriend has had a baby before. after childbirth, lots of the muscles down there get a bit "stretched out". i know some woman who pee when they laugh or cough, let alone when they're excited. i assume she's never given birth, but it still may be pee. at least you know you're getting her excited - one bodily fluid vs. the other whats' the diff? pee is pure/.sterile... so don't worry about it...