Kristen Stewart on Fifty Shades of Grey: “It’s Just So Raunchy!”

Kristen Stewart on November 1, 2012 in Beverly Hills, California. Gregg DeGuire/WireImage

After The Twilight Saga: Breaking Dawn — Part 2 comes to end, it's probably safe to say Kristen Stewart won't be looking to do the Fifty Shades of Grey film adaptation next!

PHOTOS: Kristen and Rob's romance

Although the actress has played a stripper in Welcome to the Rileys and gone topless in On the Road, Stewart, 22, is a little embarrassed by E.L. James' bestselling erotic novels. (The author originally started writing the series as Twilight fan fiction, after being inspired by Stewart's character, Bella, and her boyfriend Robert Pattinson's character, Edward.) 

In fact, she hasn't even really read the steamy book. "I've skimmed parts of it," she told Backstage magazine in a new interview. "When I read the first few pages describing her messy hair, I was like, 'This is so strange.'"

"But it's just so raunchy!" she added with a laugh. "I mean, obviously, everyone knows that. But when I see people reading it on planes and stuff, I'm genuinely creeped out. Like, you're basically just reading porn right now! Get that blanket off your lap!"

Stewart wasn't too shy, however, to play the seductive Marylou in the Walter Salles' directed film On The Road, based on Jack Kerouac's class book.

"I know it's an odd thing to say, but it didn't worry me. I really do love taking walls down," the actress explained. "I didn't want to hide, especially as Marylou — she's the last person who would hide."

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