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Few things could quell a suitor's ardor faster than Sean Penn's cranky mug. It would be like taking a cold shower while listening to Christmas carols, with any thought of romance fleeing without a forwarding address. But that's apparently the position Robert Pattinson is currently in, because word is he's dating model Dylan Penn, the Oscar winner's daughter with Robin Wright.

"They've been dating a month or two," a source tells People. "He's crazy about her."

Rob, 27, who broke off his three-plus year, Mini Cooper-marred romance with Kristen Stewart in May, was spotted with Dylan, 22, at the Viper Room in Los Angeles on Sept. 7.

As they watched a performance by rapper Mickey Avalon, "They were touchy-feely and very flirtatious," a spy tells Life & Style. "There was a level of comfort there. You could tell they've hung out a few times."

After the show, Pattinson and Penn reportedly grabbed drinks and fries at the Chateau Marmont (as you do) before heading back to the actor's house with a group of friends.

"They went into his kitchen, and he put his arms around her," relates an eavesdropping bystander, who may or may not be describing Rob's latest cologne ad. "Then he was kissing her neck and talking all lovey-dovey. It was clear they'd been out together before."

When the get-together dispersed around 5 a.m., Dylan was still there, says the tab.

Given the timing, it appears that Penn may be the mystery lady who was spotted holding hands and dancing with Pattinson at a birthday bash on Sept. 21.

It remains unclear how Papa Penn reacted to his offspring cozying up to one of the biggest paparazzi targets in Hollywood, given his history of confrontation with photographers (a trait his son, Hopper, unfortunately inherited).

"Sean has really high standards for his kids," a source tells L&S. "Any guy who dates Dylan should watch his back and treat her right!"


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