My section of the polycule (so far) is a triad-- My girlfriend lives with my boyfriend. They aren't really "romantic" in the usual sense, but they are life partners who occasionally have sexual interactions that aren't really any big deal either ("queerplatonic" is a term they have used before, also "moirails"). Their relationship is more just taking care of each other, rather than sexual or romantic. My girlfriend, I love romantically and have sex with. My boyfriend, I love in a less romantic and more "family" way, but we also occasionally have sex. He has other platonic partners that are legitimate relationships even though they are non-sexual and non-romantic. He also has separate sexual partners who he is not romantic with. My girlfriend has three other partners, besides us in the triad, whom she loves romantically at long-distance and has sex with when they are together. We don't often have sex with people outside the pre-existing relationships, but are free to do so. We are free to form romantic relationships at-will. We are all also free to enjoy BDSM relationships/activiti es with others outside the existing relationships. We all trust each other to choose safe and trustworthy partners, and we have an agreement to tell each other about risky behavior and/or medical issues. And we are the kind of personalities to not often (or ever) have anonymous encounters. We do our research/get to know new partners/whatever before anything serious happens anyway. less