Friend with benefits AND Open Relationship
After my last relationship ended I haven't been interested in love, marriage or commitment. I met an awesome college graduate and the two of us became friends with benefits. We've even gone out to parties and teamed up on guys and girls, because we're both bi.
Then in the last month or so I met someone new who feels more romantic towards me, and took a little while to get used to the notion of non-exclusivity, but is totally okay with it. Also being bi and an exhibitionist, it looks like we'll be going to parties even if we don't play with others there.
Both partners know about each other. Both are cool with it. Honesty and respect can help you get what you want!