Kelly's Plunging Top Reveals Surprising Lipstick Mark

Where does she find the energy? Kelly Osbourne and new best friend Kate Moss partied till the small hours this morning, after celebrating Chicago’s 10th anniversary on the London stage.

Kelly, 23, wore a daring plunging corset style top to the anniversary theatre performance, revealing a lipstick kiss nestled daringly close to her cleavage.

But the reality TV star was on best behaviour for dinner with Moss and her boyfriend Jamie Hince, wearing a lady-like black satin shift dress for dinner at Nobu.

Then they were whisked off to a do at fashion photographer Mario Testino’s house where they partied with the fashion elite.

Earlier that evening, Chicago performers from the past decade including Denise Van Outen reunited for a charity performance of the musical about two murderous chorus girls and a razzle-dazzle showbusiness lawyer.

Kelly Osbourne, who recently played Mama Morton, told reporters: “It’s the best thing I have ever done in my life. The story line is so before its time.”

The London revival of the musical, first staged in New York back in 1975, has survived with a constantly changing cast ranging from Hollywood stars Brooke Shields and Joel Grey to French pop singer Sacha Distel.

(Via Kiss and tell: Kelly's plunging ...)