Robert Pattinson Wants to Watch Kristen Stewart Film Sex Scenes!

Pattinson stalking Stewart's "On the Road" set.

As 20-year-old Kristen Stewart tries to keep her film prospects and character range broad, it sounds like boyfriend Robert Pattinson is on the edge. A source has indicated that the reason Rob's been hanging around Stewart's "On the Road" set is because he's nervous about the sexy character she plays...and, it's reported he's jealous of acting phenom Viggo Mortenson!

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Don't be misled: Kristen Stewart doesn't hook up with 51-year-old Viggo Mortenson in "On the Road." But the reason our pals at Hollywood Life believe Rob's a little freaked out about Mortenson is that he's "Viggo is an artistic, romantic, brooding guy like himself - just way, way older." Plus, Danish Mortenson is all-European...just like Rob. What American girl can resist?

Furthermore, Kristen Stewart's role as the unbridled Mariann Moriarty has Pattinson reeling -- said an insider, "[Pattinson] didn't like that Kristen was even considering taking this role. He understands that she doesn't want to be known as just Bella from 'Twilight,' and he's doing the same thing with his own career, but he didn't take on a role as risque as hers!"

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So how will Pattinson take action to claim Kristen as his own? The source continued, "Rob plans on being on the set of 'On the Road,' not because he has a role in the drama, but because Kristen has a real risque part! ... There are a lot of sex scenes including a threesome, and Rob wants to make sure that it's all pretend from the start and finish of the film."

Think Robert Pattinson has reason to freak out? Stay with LimeLife for all the udpates!

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