Fergie and Josh's Bedroom Dress-Up

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It seems Fergie is already gearing up for her role as a prostitute in the movie musical Nine this fall.

A pal of the “Fergalicious” singer, who will star opposite Daniel Day-Lewis, reveals that she owns a variety of sexy costumes that she uses to play dress up for fiancé Josh Duhamel in the bedroom.

Among the characters she becomes: a police officer, a dominatrix and a nurse. When Fergie, 33, showed Josh, 35, her French maid outfit, he joked, “Oh, good, you’re finally gonna clean your closet!”

A pal of the stunning couple, who are taking their time planning their upcoming wedding, tells OK!, “Fergie could not stop laughing. She says not taking themselves too seriously is the key to their relationship — and the fact that they can’t keep their hands off each other doesn’t hurt either!”

Even though Fergie isn't shy about telling OK! about her plans in the bedroom, she likes to stay private about wedding plans. "That's the one thing I can keep secret in my life," she coyly explains.