The story is short and it was contained in a bigger "book", so there is this couple that go on a trip or something like that, they stop in a forest (or in a place that is outside) and are seen by two guys that kidnap them, when the boyfriend wakes up he find himself tied up in a room and sees the two guys trying to fuck his girlfriend, she accepts because they are threatening to hurt the boyfriend but only if they don't show him how they are gonna fuck her, in the end they fuck her and maybe release them i don't remember the end very well.