Tildos, I have a problem.

So, my wife is a huge film buff. However, there is one movie that she had repeatedly rented from Hollywood Video sometime in the early 00's that she has been unable to recall or find, despite all advances in search engine technology.

This would be filed under the 'formative pre/early teen latchkey girl sexual awakening' moments. So she can't really remember much beyond the favorite sex scene, and even then details are scarce. Can crowdsourcing solve what 15+ years of searching has not?

Fragments discovered so far list:

• Not pornography. Probably legitimate film, not skinemax.
• Scifi/fantasy of some sort. Costumes described as "waterworldesq, but not waterworld."
• Scene probably takes place in a desert
• She is sleeping with some other dude's friend
• Missionary. He's loud, and at one point she bites his nipple.

I know. Not much to go one, especially since almost all remembered details highly overlap with porn results.

Other films that have already been well worn by this point:

• Tank Girl
• Waterworld
• The Fifth Element
• Barbarella

Edit: After 2 weeks, @myrrh solves our mystery