I'm a member of a triad that looks like it might be headed towards adding a fourth member. We were (and are) a group of four friends - two of us started dating about ten months ago, then the third joined about three months ago, and now maybe the fourth will too. The three of us currently in a relationship are all dating each other (complete triad), and the fourth person would be dating two of us, and has a close (almost romantic) friendship with the third.
I've been reading about quads on this site and others, but almost everything I've found has been two pre-existing couples joining together. Does anyone have experience or advice about quads not formed by two couples, and/or quads where all members have relationships with all other members, not just with the two opposite-sex members (as in the two heterosexual couples model that I keep reading about)?