I’ve never really cared too much about Miis. I never even made one for my Wii or 3DS — hell, I’ve never even opened Street Pass. The only reason I made a Mii for my Wii U was because it was part of making an online account.
In Nintendo’s wildly popular sim Tomodachi Collection: New Life for the 3DS, there is a bug that apparently enables male Miis the ability to marry other male Miis. Apparently, make that, enabled.