Why do they put a sheet between couples during sex scenes in movies?

Even if they show everything why do they still put a blanket or sheet between them?Why do they put a sheet between couples during sex scenes in movies?
it's hollywood. they dont know what their standards areWhy do they put a sheet between couples during sex scenes in movies?
I've never heard of them doing that, but if they do it, I'm sure it's because it makes the actors feel much more comfortable, especially the ones who are married and don't want to be rubbing their body against anyone but their spouse, and I can't blame them.





David Fincher (he was the director of Fight Club, among many others) he actually hates using the actual actor for sex scenes, so he animates all of the sex scenes by using sensors and then CG. I thought that was kinda cool. It made me actually go watch the sex scene in Fight Club (I always look away).
1.part of the bed, you cover yourself with a sheet


otherwise it can easy look like a p';';';n ,if there are no sheets,blankets


and it can make the scene more interesting/drama, till you get to the


sex scene


2.luxury bed sheets can lift up a romantic part in a scene