Spread the word: Kardashian mayo talk is TMI

Another TMI moment from the Kardashians.

On "Conan" Thursday, Kourtney said Kim is "horrified" by her and their sister Khloe. The reason? Her sisters once said on their E! reality show that they put mayo on their private parts.

"Talking about putting mayonnaise on your thing is not appropriate advice," she told them.

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Khloe then chimed in, "Honestly, women need to know how to take care of their stuff."

Kim interjected, stressing to the audience that her sisters were just joking.

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"How do you know?" asked Khloe.

Kourtney then added, "People asked us, 'What does mayonnaise on your vagina do? And we said it makes it shine like the top of the Chrysler Building. And people were like, 'Why would you want a shiny vagina anyways?"

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Conan was speechless.

"I don't know, uh ..." he began. "Wow, anyway ..."