WENN 2 / 11
WENN 2 / 11

Khloe Kardashian made her debut as a co-host on "The X Factor" on Wednesday night, but it likely didn't make the first impression she had intended.

Taking the stage alongside Mario Lopez to helm the FOX hit's first live show for Season 2 -- featuring performances by the top 16 contestants -- Kardashian, 28, exposed her left nipple through a sheer purple blouse.

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"I think I had a little nip action earlier," the reality star tweeted during the show, in response to judge Simon Cowell's joke that the Los Angeles studio's air conditioning must have been "on high tonight."

Appearing to have covered up midway through the broadcast, Kardashian poked fun at her indecent exposure when bantering with Cowell, 53.

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"May I say, Khloe, you're looking sexy tonight," Cowell told Khloe, Lamar Odom's wife, who completed her "X Factor" ensemble with a black skirt and heels. "The air conditioning is on high tonight. It's very distracting!"

"You love it!" shot back Kardashian, fully aware of what Cowell was referring to.

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Aside from her playful banter with Cowell, Kardashian made awkward small talk with the show's contestants, including Diamond White, in between their performances. When Lopez teased the 13-year-old singer about having a boyfriend, White told him she was single because "my mom would kill me" for having a boyfriend. "Don't let your mom kill you," Kardashian replied to a confused-looking White.

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Named as a co-host for "X Factor" just two weeks ago, Kardashian was admittedly nervous going into the reality competition's live shows. "I've never hosted before!" the star said during a recent interview with KIIS-FM's Ryan Seacrest. "What if I get kicked off the show because I say something so bad? That's what I'm nervous about, but I can't be anybody else but myself. I just have to control the language a little bit."


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