Relationships can have many levels of closeness and intertwinedness — from casual fuckbuddies to regular, serious girlfriend or boyfriend to long-term live-in life-long committed partners. The category that we think our relationship falls into affects the way we interact with that partner today and the vision we have for the future of that relationship. In the monogamous world, we talk about dating someone casually or say that someone is marriage material. In the poly world, people talk about primary and secondary relationships.