'KUWTK': Khloe Kardashian reminds Rob about the time he allegedly had sex with a Kim Kardashian lookalike

Sunday's all-new Keeping Up With the Kardashians brought family awkwardness to a whole new level when Rob and Khloe Kardashian took a bizarrely uncomfortable walk down super-gross memory lane.

Rob came to Khloe's house to hang out, but Khloe was still in bed, suffering from menstrual cramps and a fever. She invited Rob to come lay next to her, and things got off to a strange start when he tried to spoon her.

And that was maybe the least-weird part of their time in bed together.

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As Rob took her temperature with the back of his hand pressed to her forehead -- and then tried to stroke her face -- Khloe raised a question, seemingly out of nowhere, asking her brother, "Do you remember when you f**ked the girl who won the Kim Kardashian lookalike contest?"

See photos of Rob Kardashian:

Instead of immediately denying this claim or retching in total disgust, Rob awkwardly laughed, and then tried to change the subject to another girl who showed up to Khloe's house, naked, had sex with Rob and then, as he so eloquently put it, "period-ed" all over her bed.

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Khloe -- who admitted she "kind of" remembered that incredibly memorable story -- then made everything even weirder when asked the one question literally no else was thinking: "Why didn't you ever sleep with someone who won a Khloe Kardashian lookalike contest?"

See photos of Khloe Kardashian:

Needless to say, after the episode, viewers had some questions -- or, well, one question which could basically be summed up as: "Wait, what?"

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Later in the episode, Khloe made Rob experience what it was like to endure menstrual cramps through the use of a fancy electric muscle simulator, because, at this point, why not?

Check out the video below for a look at some other (less disturbing but still awkward) family drama from Sunday's Keeping Up With the Kardashians.