Wait… Monster races have same sex relationships, because they don’t have marriage? No, that’s not it. Humans and other “player races” have most iconography depicting Male and Female marriages. So for some reason those races have limited their relationships based on it being the most- “Normal”? How does that work? So conforming to society is the cause? But real people don’t work that way- oh right… They aren’t “real” people. So how things work for them are bound by certain rules and changes. If one thing is default that’s how it is, until something is changed on a deeper level.