In case you've been living under a rock, Fifty Shades ofGrey is the best-selling book by British author E.L. James, and is a steamy, reportedly Twilight-inspired tale of a virginal college student, Anastasia Steele, and a handsome billionaire, Christian Grey. Imagine your dirtiest Bella/Edward fantasy with a BDSM twist. (BDSM, by the way, is a catch-all term for sexual bondage, sadomasochism, dominance and submission.)

What's amazing is the speed at which this book, which is number one on the New York Times digital bestseller list, is taking over the iPads and Kindles of mild-mannered mamas all over America. Apparently, this is a little bit of just-what-the-doctor-ordered. Maybe it's the fact that with all our digital readers, we can consume this stuff without being judged by the woman sitting next to us on the subway. Or maybe it's that Twilight has primed us all for some let-our-hair-down erotica where things get taken just a little bit, um, further.

Whatever it is, sex therapist and author Sari Cooper says it's all a really good thing, because it's helping women wake up and acknowledge their own fantasies and desires. Plus, she adds, erotic novels like Fifty Shades of Grey can help improve your relationship or marriage by opening up a conversation about sexuality. "For most women and many men, they don't have the language to articulate what they want in bed. If they have a book like this, they can point to a scene and tell their husbands: 'See that? That's what I want you to do to me'."

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So 'fess up moms: Are you reading Fifty Shades of Grey? Do you love it?

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