We're swingers.
Neither of us really connect sexual activity with romance. As an example, one of my male friends is Bisexual and he has a girlfriend, but I'm his male friend with benefits. Also, not a lot of the places that hire around here accept homosexuality, so sometimes, lots of men (or at least that ones I know) try to keep their sex life hidden from their friends and coworkers and friends with benefits covers that up.