Kendall and Kylie Jenner’s Secret Handshake Includes Boob Slapping: Watch!

unrehearsed. no no @kyliejenner

A post shared by Kendall (@kendalljenner) on

Sister shenanigans! Kendall and Kylie Jenner showed off their, um, quirky handshake via SnapChat on Monday, January 4.

Kris and Caitlyn Jenner's daughters shared the hilarious videos on Kylie's personal account. They stuck out their tongues, smacked each other's hands and pretended to go in for a kiss on the lips.

At one point, Kendall (blink and you'll miss it!) slapped Kylie's chest with her hands three times and twerked like crazy à la Miley Cyrus.

"unrehearsed. no no @kyliejenner," the model, 20, captioned a clip via Instagram.

Kendall Jenner and Kylie Jenner
Kendall Jenner and Kylie Jenner at the Kendall + Kylie fashion line launch party in 2015. Jason LaVeris/FilmMagic

The siblings appeared to be at a party with several pals at the time. Kendall — who was spotted in St. Bart's with her ex Harry Styles over New Year's Eve — wore an off-the-shoulder top and Yeezus hat. Kylie, 18, cut loose in a tight long-sleeve top and later accessorized with a gold crown.

Watch the videos above!

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