Sex: movies vs. reality
One of my favorite movies is "Taxi Driver", but I don't think there's any danger of me going on a vigilante rampage to save a child prostitute. I really like "Apocalypse Now", but there's absolutely no danger I'm going to float down the Mekong delta in a PT boat machine-gunning Cambodians. When it comes to S-E-X though, people have a heart attack that viewers are all going to follow whatever perverse, deviant content they see in movies like "The Dreamers", "Last Tango in Paris", "Nymphomaniac" or even something relatively tame like "Blue is the Warmest Color".
Look, it just wouldn't be interesting to make a movie about the vanilla sex the average IMDB user enjoys with his or her significant other. They make movies about rather extreme and deviant sexual relationships, like they do about war or murder, because it's more INTERESTING. I don't think anybody's taste in sexy movies really says ANYTHING about them sexually or otherwise. Even if this movie is a sex fantasy for some people, so what? Eva Green is one of the few females actually prettier than Michael Pitt and Louis Garrel, so it's an effective three-way bisexual fantasy. And there is no actual "incest" even in the context of the movie. And it is a MOVIE. Garrel and Green are not REALLY brother and sister. There is nothing less healthy than to expect fantasy, fiction, and art to strictly conform to the moral dictates of mundane reality.
But nobody does that with anything but S-E-X. I don't really want to do my real-life sister, but I don't want to murder anybody either, but that constantly happens on TV or in PG-13 Hollywood movies. I'm sorry, but there is just a lot of unnecessarily judgmental prudishness when it comes to sex.
"Let be be finale of seem/ The only emperor is the Emperor of Ice Cream"