text: I know straight couples who do it.  I'm in one. For me sex has always been casual and fun, not really tied to love or romance. We're in our 20s and look good, we still are attracted to other guys, and we like to go out and pick up boys either together or apart (sometimes our tastes diverge). We keep not excessive, and at the end of the day, we live together and come home to each other (with stories, usually). It's fine, not for everyone, and also not for every relationship. I probably wouldn't do this in any other relationship, but it works here.