i tried it once with an old gf and my friend and i found it quite bad cos she decided to dump me and fuck him instead - after the threesome (she split up with me and got with him) i would try it again. on another note - my brothers girlfriend said she really wanted to get hold of me and my gf (who is bi and its ok with me) and i dont know what to do cos both me and my gf wanna do it but we cant cos its my bros gf