Star Magazine is reporting that Jessica Simpson and John Mayer are fighting over the fact that she’s been going out baring her assets. John is mighty annoyed at how sleazy she’s been looking lately and does not want her to go out in LA to hang with her friend at nightclubs, they claim.

Jessica and John have been together all of eight months and this latest row is said to be threatening their unlikely relationship:

Jess, 26, “misses her friends in L.A., and the easiest way to see them all is to hook up at a club,” says an insider. But John, 29, “can’t stand the nightclub scene and all the superficiality that goes with it,” says a source close to John. The singer was “furious” when Jess was snapped in a cleavage-baring dress while club hopping in L.A. on April 16, says the source. And the two had fought earlier about her May 4 appearance with the Pussycat Dolls in Las Vegas.

“I believe John asked Jess to think about what was more important to her - partying or their relationship.”

The decision may be easy once John ends his world tour on August 8. He is NYC-based while Jess is not an L.A. girl.

[From Star Magazine, print edition, May 14, 2007]

If that’s true and more than just guesswork on Star’s part, John couldn’t have been thrilled with the boob-baring outfits Jessica wore to her Pussycat Dolls gig and to the Costume Institute Gala last night. She looked like a gothic mess in dresses that showed off her store bought assets.

Here are John and Jessica at the Costume Institute Gala. They look mildly annoyed. First two pictures from SplashNews.