I have a childhood memory of seeing this in a science fiction show/movie... it would have been a super long time ago, but the scene just popped into my head and I have very little clue what it's from. Let me know if it rings a bell... A guy (maybe from the present) is with a girl (I think from the future?) -- and she casually asks him if he wants to have sex. Somehow a proposition is made, and when he starts to strip down naked she totally flips out and leaves, because apparently "sex" in whatever time this is is done virtually (and isn't a very big deal). She is completely disgusted and shocked that he was thinking about real sex. I don't think I made this up... it has to be from something!