I disagree, Fifty Shades is not about BDSM by mature consenting adults, it's about the emotional domination of a naive, psychologically submissive girl by a creepy and controlling sadist. When she finally, out of love, lets him beat her, she hates it so much she leaves him.This is not 50 shades of gray. 50 shades of gray is fan fiction about two CONSENTING adults engaged in BDSM.
Edit: whereas, in real life, the Ana's of this world don't leave.