Credit: Kevork Djansezian/ Getty Images, Michael Kovac/ Getty Images Photo: Derek Hough and Jennifer Gimenez

Dancing with the Stars hunk Derek Hough had a steamy pas de deux recently — but it wasn’t with rumored girlfriend Lauren Conrad! Instead, it was sexy Celebrity Rehab star Jennifer Gimenez who caught his eye the night of Oct. 29.

Jennifer and Derek were first spotted together that evening at a private Halloween party at the Standard in Hollywood. Jennifer and BFF Brandi Glanville — both scantily clad in revealing, lingerie-based costumes that showed off their assets — arrived together. (According to both of their Twitter accounts, Jennifer will be joining Brandi for a multi-episode appearance on Real Housewives of Beverly Hills later this season.) Derek, meanwhile, dressed in a suit, came with sister Julianne and a few pals. Once Derek saw Jennifer, he made a beeline for her, according to an eyewitness at the bash. "They greeted each other warmly. It was clear they already knew each other," the eyewitness tells Wetpaint Entertainment.

Things really started to heat up later that night when Jennifer and Derek hit a second party at LA’s Roosevelt hotel a few hours later. "He was all over her," a second eyewitness who was at the Roosevelt tells us. "He was dancing sexily with her and pulling her close. They were very touchy-feely. They looked like a lot more than just friends."

One person who might not be so happy about Derek and Jennifer’s canoodling? Lauren Conrad. Although both she and Derek denied a romance, they'd been spotted holding hands and looking cozy all over town since early September. In fact, they were seen making out in public as recently as Oct 17 — less than two weeks before Derek made his move on Jennifer.

Don’t worry Lauren, there are plenty of other fish in the sea!

Calls to Jennifer’s rep were not returned. Derek, through his rep, says he has met Jennifer a few times through mutual friends, but that is the extent of their friendship.

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