What is she hiding under there? Lauren Conrad partied in a black bikini at Tao Beach at the Venetian Hotel and Casino in Las Vegas on Saturday, but she left a little to the imagination with that cover up.

"The Hills" just celebrated its final season, and Lauren and Kristin Cavallari have made amends after a tumultuous friendship (they both fought over Stephen Colletti and dated Brody Jenner.)

Cavallari explained, "We are not going to lunch together and I don't have her phone number, but we are cool."








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