I'll admit it: I learned about sex from science fiction. Sometimes that was confusing. For example, it turned out that there aren't any half-hominid, half-horse creatures with three sets of genitals, as there are in John Varley's Gaia series. Nor do humans have sex with sentient disembodied genitals, as they do in Rudy Rucker's The Sex Sphere. Still, these books were educational in their own ways. (When I met Rudy Rucker a few years ago, I told him about how his book had been a sex education tool for me in junior high and he gave me a special autographed copy in which he'd drawn a picture of one of the floating breast/pussy alien things. Thanks, Rudy!)
Despite a few setbacks, I managed to cull enough knowledge about sex from sciencefiction that I was ready to get my swerve on with humans when the timecame. I'm pleased to say that you can still use SF to find unusual (or imaginary) sexual information today.
For example, there is the vast repository of robot and superhero stories at the superlative Erotic Mind-Control Stories Archive, run by the mysterious Simon Bar Sinister.
Perhaps you don't have any educational goals in mind, and you just want to see a semi-naked cylon.
If you're of a particularly intellectual bent, and enjoy sly jokes about Western metaphysics, you can pick up a copy of Supervert's diabolical book Extraterrestrial Sex Fetish.
