#5 The Relationship Matrix: Quadrant I and Mono-Poly

5 Swingers - While in a singular, committed marriage, it is one open to purely sexual extramarital relations.

6 Mono-Poly - The monogamous partner results in the point near the X axis in quadrant IV because they themselves are monogamous but allow for an open arrangement with the other partner. The poly partner is marked close to the x-axis in quadrant II because in this scenario the mono partner prefers they neither randomly hook up nor share great commitment with anyone else.