Fifty Shades of Grey
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I really like the story line, however unbelievable it is. Ana and Christian are great characters and they were written quite well.
I do have one big issue with the book. When describing sex scenes Ana will say ...now he's touching my sex... I have to assume that when she says sex she means vagina, but I'm thoroughly confused about that. Maybe different cultures/countries refer to the vagina as sex. But I've never heard that.
On an emotional/relationship level I think that these two are just like any couple, just trying to work through the hard stuff to have the good.