What lesson/s that you get from Fifty Shades of Grey?

My friends on social network, like twitter and facebook "said" the book is really good.
I know the book is "sexy", they said so, but apart from the sexy things they "do",
is there any GOOD lesson/s I'd earn from it. Some gets tempted to read it though
but a bit scared at the same time that it might turn you into something you're not?
... lol

watcharee 4EN 053