Screw that, have there only be civil unions, and let people refer to it with whatever nickname they want to use. Marriage, Kekkon, whatever. Marriage isn't always a religious thing, and generally was used as a purely political/financial maneuver. It's a property transferance ceremony. Only recently did it acquire this notion of "love" being involved beforehand. (Probably set up by the same people that make you think that diamond rings are some sort of time-honored tradition.) There should be no benefits or perks or downsides associated with being married, with regards to the law. The only thing it should cover is those "next of kin" things and wills and such. And as such, it shouldn't care whether you marry a man, a woman, or triplets.