Khloe Kardashian Grinds with Jessie J, Taylor Swift at the 2014 AMAs: Watch!

Khloe Kardashian got in on the musical action at last night's 2014 American Music Awards — grinding with Jessie J as she performed her hit song "Bang Bang" — and even smacking the singer on the butt!

The sexy reality TV star was seated at the end of a row at Los Angeles' Nokia Theatre for the Sunday, Nov. 23 high-octane award show, next to her sister Kendall Jenner. And when Jessie took her hit song (which she performed mostly on stage with Ariana Grande and Nicki Minaj) down into the audience, she made a beeline for the 30-year-old Kardashian sister.

Wearing a tiny, Versus by Versace LBD, Kardashian started dancing along with the chart-topping singer, thrusting her butt out in Jessie's direction. While her shocked sister Jenner put her hand to her mouth in disbelief, Kardashian then started grinding with the performer, before giving her pal's booty a cheeky slap as she walked away to find another dance partner.

Evidently enjoying the audience participation, Jessie made her way towards Taylor Swift, who happily obliged with her own bit of booty shaking.

 

Jessie J performing Bang Bang
Jessie J performs Bang Bang with Nicki Minaj and Ariana Grande at the 2014 AMAs Kevin Winter/Getty Images

The brunette singer, who was dressed in a skintight jumpsuit, then wiggled her way a few seats down to where Lorde was standing, for a couple of sexy moves with the New Zealander.

Watch Jessie's entire star-studded grind-a-thon in the video above!

Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics and more delivered straight to your inbox!

Want stories like these delivered straight to your phone? Download the Us Weekly iPhone app now!