I write menages, MM, and FF. I like to read all different kinds of books so that's the way I write.
Several of my menages are series like the "Raw Claiming" books ("Raw Craving", "Raw Need" and "Raw Want") or the "Possessive Passions" series ("Shared Possession", "Possess Me" and "Ultimate Possession".)
For each of these series I began by building a world where there was a specific reason why several men would marry and share a woman. One menage story is eminently believable, but when a whole society is living in that way, I needed there to be a reason why they'd chosen to do this. Hence the traditional beliefs in the "Possessive Passions" series, and the end-of-the-world scenario in the "Raw Claiming" series.
How do you feel about menage stories? Do you need there to be a reason for people to act this way, or is lust a good enough reason for you?