Robert Pattinson's on-and-off girlfriend Kristen Stewart was not happy to see photos of the 'Twilight' hunk making out with Emilie de Ravin.

Pattinson and 'Lost' star Emilie de Ravin have been filming their upcoming movie 'Remember Me.' Last week the costars shot romantic scenes in which the two were rolling around on the beach kissing. The sexy stars appeared to be enjoying themselves, even when the camera wasn't rolling.

A source tells OK, "Everyone else was setting up for the next shot, but Rob and Emilie stayed where they were. Emilie snuggled with him for at least 10 minutes. She was sitting with part of her body pressed up under his arm and they were making each other laugh. They're definitely getting close — you can tell it's more than a work relationship."

Stewart was reportedly not happy to see Robert with another woman, an insider claims, "She knows screen kisses are part of Rob's job, but it doesn’t make things easier, seeing sexy photos of him and Emilie in full lip-lock." Another friend added, "Kristen saw a photo of them kissing and flipped out!"

Adding fuel to the fire is gossip that Robert and Emilie have been spending plenty of time together off set, including numerous sightings at trendy clubs and restaurants.

"They spent a lot of time telling jokes, laughing and whispering in each other's ears,” said an eyewitness to a dinner at The Bowery Hotel's Gemma. "At one point Emilie took Robert's Ray-Bans and was playfully wearing them before putting them back in his shirt pocket — it was very flirty. Rob was so sweet and attentive; if I didn't know anything about him, I would think Emilie was his girlfriend!"

Who do you think is better for Robert: Kristen, Emilie or YOU? Leave a comment below!

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