From a practical point of view I don't see a downside of what happened: phil gets sex, the girl gets sex, the girl is forced to think about what she did and will decide most likely to either a) to leave current BF or b) discovers how much she really likes him and stays faithful in future. If girl selects plan b then BF realises hes and uber chode and googles "how to pick up girls", does some reading, finds this forum, realises he needs the man the fuck up, finds another GF and this time keeps her faithful due to his new found awesomeness.