Red-hot ... twins Kristina and Karissa Shannon have signed up for Celebrity ... - The Sun

The American twins have promised bosses they will steam up the series.

And it is hoped that ladies' man housemate Kirk Norcross from The Only Way Is Essex, will be the perfect "victim" for the 22-year-old pair.

Centrefolds Kristina and Karissa spent two years as the live-in girlfriends of Playboy founder Hugh Hefner at LA's Playboy Mansion before moving out last year.

An insider for the Channel 5 series, which kicks off on January 5, said: "The girls have pledged to really sex up the Big Brother house. Kirk won't know what has hit him.

"But with his ladies' man reputation, he is sure to be tempted by our Playmates."

The girls also have a tougher side ? both were put on probation in 2007 for aggravated battery during a fight at a party.

Playtime ... bosses hope the girls will catch TOWIE star Kirk Norcross's eye

Karwai Tang/Alpha Press

Karissa was arrested again for a second alleged assault later that year.

Other celebs set to enter the house include Boy George, Ryan Giggs' sister-in-law and ex-mistress Natasha Giggs and Loose Women's Denise Welch.

Bunny business ... the twins with ex-love Hugh Hefner

Polaris / eyevine

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