Kourtney Kardashian Couldn't Hide a Hickey From Her Eagle-Eyed Sisters

Kourtney Kardashian couldn't hide the evidence of a recent makeout sesh from her sisters in a scene from Keeping Up with the Kardashians.

In a clip of an upcoming episode of the reality series, Kourtney is seen in the kitchen spending time with Kim and Khloé, both of whom are seen grilling their eldest sister about her love life, and where what an apparently large hickey came from.

"Kourtney, what is this hickey?" Kim questioned in the clip, clearly alarmed by the scandalous mark. Khloé leaned in for a closer look, since Kourtney's shoulder-length locks were apparently in the way.

"What is on your neck?" she asked, as Kourtney nervously smoothed her hair. It's impossible to see said hickey from the camera angles, but Kourtney was clearly trying to play it cool in the video.

"My hair is here," she said sheepishly, unable to hide the huge grin on her face.

"Who on earth would you get a hickey from?!" Kim asked incredulously, which prompted a flustered Kourtney to ask her sisters to back off in a playful manner.

"Just let me live my life! Don't analyze," she pleaded, jokingly.

"Who gives you a hickey like that?" Khloé pressed, clearly trying to get to the bottom of the situation.

"I think I know who it's from," a smug Kim replied, and the clip cut away to Kourtney.

"My sisters are pretty nosy when it comes to anything in my life. I don't know if they're bored in their own lives and they want to live through my wild dating life that they think is going on. Come on guys, let's get it together," she spilled during a confessional segment after the scene.

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The question still remains, however: whomst, indeed? Where did the mystery hickey come from, and will we find out on the next episode of Keeping Up with the Kardashians?