Create very advise you to wade and read so it, but basically they precipitates into the five different kinds of monogamy that can be somewhat additional depending on perspective. It refer to y, that is merely writing on relationship ranging from merely two people. They reference social monogamy, that is particularly regarding the two people deciding to live together and you can cooperate. This is how they place it. Cooperating and getting basic info like defense, restaurants, and cash.