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Though they have yet to publicly address dating rumors, Sean Penn and Charlize Theron certainly aren't trying to hide their new relationship. The A-Listers rarely left each other's side at Penn's third Annual Help Haiti Home Gala, which was hosted by the "Secret Life of Walter Mitty" actor's charity.

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Theron, 38, who brought her mother Gerda with her, was seated next to Penn, 53, and looked fierce in a short black cocktail dress. An eyewitness says Penn spent much of the night introducing the South African star to all kinds of people.

The rumored couple was openly affectionate throughout the night, holding hands, putting their arms around each other, and cuddling at the table. At one point, Penn even kissed Theron's neck, cozying up to his new love. When Bono and The Edge gave a surprise performance, singing "Hallelujah," Penn had his arm around the "Prometheus" actress the entire time. Bono also reunited with U2 for the first time in four years, singing "Vertigo" and "Desire."

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Penn's rumored love also got into a friendly bidding war with Coldplay frontman and Gwyneth Paltrow's husband Chris Martin over a Banksy print shaped like a heart. Ultimately Theron lost, and Martin took home the art for around $650,000.

But Theron and Penn's romance was the talk of the event. The duo recently vacationed in Hawaii together and were spotted last week going to see "The Wolf of Wall Street" in Hollywood.

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"It looks serious and comfortable," the eyewitness continued.


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