Host Jay Leno gestured to the very pregnant Kourtney Kardashian and joked, "You’ve really let yourself go." To which she replied, "I know -- too much In-N-Out."
Ooops! Kim Kardashian tried to cover up her sister's inadvertently dirty joke, but only made it worse. "Five Guys," she interjected, "Five Guys."
Badum-bing! Leno quipped: "I assume you’re talking about the hamburger."
The smut continued when the sisters gave Leno a gift of a cat bed, fully equipped with their own linen. He took a black light to it to check for stains.
Season 7 of "Keeping Up With The Kardashians" premieres Sunday, May 20th at 9 p.m. ET on E!. "The Tonight Show" airs weeknights at 11:35 p.m. ET on NBC.
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