(CBS News) The erotic book, "Fifty Shades of Grey" is now a best-seller because women who can't put it down are sharing it with just about everyone they know.
The novel by British author E.L. James tells the story of a virginal college student seduced by an older chief executive officer. The book's being called "Twilight for moms." But there's nothing PG-13 about it.
Sari Cooper, a sex and relationship expert, said of the book, "The more graphic domination, submission sex scenes, I think that's why it's creating more of a buzz. What woman are saying is, 'This is so hot.'"
Mostly through word of mouth, the novel and its two sequels, "Fifty Shades Darker" and "Fifty Shades Freed," have topped the New York Times e-books chart.
Cooper said, "When women enter their late 30s or their 40s, they come into their own sexually, they're more willing and confident to start thinking about what they want, especially if they've been in a long-term relationship. So maybe it has hit that group and they happen to be at that age, so that they're really willing to be able to talk about it."
(CBS News contributor Lee Woodruff spoke to a group of women about the book, and how it's changing attitude about sex in the suburbs. Watch Woodruff's report in the video above.)