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This should be a basic tenet of twin-sisterhood: Never let your matching half cozy up to a guy who's known for baring his nipples in mesh shirts. Yep, we're looking at you, Mary-Kate Olsen.

According to the New York Daily News, Ashley has once again been keeping company with long-ago hookup Jared Leto. Seems the pair, who purportedly enjoyed a brief entanglement in 2005, had "a very flirtatious meal" on Sunday night at the Polo Lounge in Beverly Hills.

Seated in a cozy booth, Ashley, 25, and Jared, 40, "couldn't stop touching each other" as they chowed down on salads, says the paper.

The ageless actor-turned-30 Seconds to Mars frontman even tried out a few of his patented wooing moves by fondling the fashion mogul's hair, stroking her arm and "playfully" jabbing her with his fork (that last move may need work).

Leto, who has dated the likes of Cameron Diaz, Scarlett Johansson, Lindsay Lohan and Isabel Lucas, reportedly picked up the check. That earned him a hug from Ashley, who then "put her head on his lap."

Olsen's rep didn't respond to our request for comment on the reunion rumors, which come four years after their last interlude.

In early 2008, Ashley and Jared were seen locking lips at a Los Angeles bash, although her rep insisted at the time that they were just friends.

Olsen, who sat with Leto at Kanye's West runway show during Paris Fashion Week back in October, has been flying solo since calling it quits with Justin Bartha in March 2011 after more than two years of togetherness.


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