Reddit reviews Unquenchable Fire

You might be interested in Unquenchable Fire by Rachel Pollack.

It's not exactly scifi in the sense that you're thinking of, but it's set in an alternate reality where society has progressed along entirely different lines. I think it may have been heavily inspired by LSD. The book is just batshit weird, but it is an interesting read.

Also, try Ursela K. Leguin's The Left Hand of Darkness. It deals heavily with gender issues and how they relate to society, as it's set on a planet where the inhabitants cycle regularly between male and female.