Been in the situation. Wasn't asked to join. To be fair, the guy was my brother. His girlfriend was an exhibitionist and insisted upon it. I wasn't a willing viewer/listener but whatever. Doesn't really bother me that much. What's wild is she apparently insisted on doing the same thing with her brother. I mean with my brother, but with her brother watching/listening. Yeah, that chick was something else. I feel like I coulda got a piece if I wanted. Like she might have been cool with me joining in. But my brother wouldn't have been and I'm not gonna do my bro like that.