Don’t forget Al Green…and some Commodores slow stuff. I love that old R&B for groovin’.
“Passion”, Peter Gabriel’s soundtrack to The Last Temptation of Christ goes extremely well with candles, incense and freaky massages.
Also, attempts to romance painted goth women can be facilitated by judicious use of The Sisters of Mercy’s “Reptile House” EP. At least that was the case in the late 80’s/early 90’s … I have no idea what the spooky kids are listening to these days.
Well, not the worst typo you could’ve made there… 
Miles Davis’ “X-Rated”
The Cocteau Twins’ Treasure
Sex-O-Rama 1 & 2
101 Strings’ Sounds of Love and Exotic Sounds of Love
How about **Blowfly[/], anyone?
Oh good, I thought I was odd for thinking that was a great make-out song.
This is very true… But then you would have all though I had something else on my mind other than music. 
I wholeheartedly endorse these.
Along with Cocteau Twins’ Treasure, Heaven or Las Vegas works well, too.
Serge Gainsbourg’s Comic Strip
Massive Attack’s Mezzanine
A little off the beaten path, but Smashing Pumpkin’s Adore can do it for me.
Black Box Recorder’s The Facts of Life (Sexy!!!)
Any of Frederick Chopin’s Nocturnes (Particularly Op. 9, nos. 1 & 2)
Beethoven’s Ninth. (I worked with one girl who took this so seriously, that she said she would not have sex to the famous “Ode to Joy” part unless she expected to marry the guy she was sleeping with.)