I agree with this. I like separation between me and any other guys but sometime accidents happen and I just try not to panic. But I know other guys that just don't seem to care. They'll put their dick right into my GF's mouth while another guy's is in there. Some of my friends do some stuff that I would consider pretty bisexual but they would NEVER say they are bisexual. Like you said, I don't know if it's because there is a female involved, they just get caught up in the moment, etc but I think bisexual might mean something different to a lot of people.