And there were no variation of this, ever? We’re talking about human beings here, where one perversion is never enough. Even so, the ancient Greeks and Romans had to know, or at least strongly suspect, that such a scheme as homosexual marriage would have wrecked their whole societies. And even their “constrained” proclivities likely had something to do with their overall downfalls anyway.
I can’t say there was no case of two guys considering themselves “married”. When Nero, I believe, had his lover castrated and married to him, they still did fertility rites to try to turn the kid into a woman.