Aside from "Yakety Sax," what do we think? Music used to be just as much a sex prerequisite for me as finding a partner with a nice ol' dickhole, but lately I've been working more with either "deathly silence" or "the sound of my dog eating something she found in my backpack in the other room," and that's a real shame. Music and sex are a great combination, perhaps the best combination, but it's tricky: if you don't feel like being super intimate but all of a sudden the Rhye album is on, there's not too much you can do.
There are some safe bets here, I think. The Frank Ocean/Miguel/D'Angelo realm is a good one. I've favored the XX and their ilk before, even some Explosions in the Sky stuff when the heart was particularly full. In the indie-rock and electro regions, these songs by Sir Sly and Until the Ribbon Breaks are immediately sex-suggestive to me. What about you? People out there who hate R&B but love sex: what do you couple to?