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Comedic cutie Paul Rudd is playing an uptight character in his new film I Love You Man, who’s having trouble getting in touch with his dirtier, more masculine side. And here he is with his co-stars of the film on the red carpet for the premiere. But the reformed frat boy reportedly has never suffered from that particular problem.

An old friend of his revealed in an interview with Time magazine, “He always liked to get naked. Anybody that lived in his fraternity house would tell you. And yes, he is a frat boy, no matter how much he would go screaming from that now.”

And that move he did as a backup dancer for Beyoncé in their SNL skit together last November in which he shoots guns with his hands while intermittently slapping his rear end used to be “his preferred method of exiting a room,” according to Page Six.

But these days, it seems Paul’s a little more shy. Shame.

Gallery Info: Paul Rudd, Jason Segel, Rashida Jones, Peggy Lipton, Jason Bateman, Jon Hamm, Jennifer Westfeldt, Rex Lee, Stacey Keibler, Sarah Burns, Jon Favreau, Audrina Patridge, Elizabeth Banks, Jamie Pressley, Niecy Nash, JK Simmons, Sarah Silverman, Lou Ferrigno, Christopher Mintz-Plasse, Andy Samburg, Jack Black, Ben Stiller, Christine Taylor, Krysten Ritter, Tommy Davidson and Kevin Zegers at the premiere of I Love You Man.