She may not have the most famous butt in the Kardashian family, but that doesn't stop Kendall Jenner from flaunting it.

The 19-year-old model bared her booty at a fancy masquerade ball held in honor of designer Roberto Cavalli's wife, Eva, on Friday at One Mayfair in London.

WATCH: Kendall Jenner Poses Topless: 'I'm Washing Away My Sins'

Jenner looked very chic, wearing a navy bralette and a sheer lace skirt over high-waisted briefs -- which hardly covered her backside. She topped off the look with a velvet blazer.

Click here to subscribe to FOX411’s YouTube channel

Inside the party, Kendall was joined by her best friend and fellow model, Cara Delevingne. The two were both photographed wearing matching lacy masks to fit the party's theme.

WATCH: Kendall Jenner Bares Her Booty at Paris Fashion Week

Cara's sister, Poppy, was also in attendance, and the three snapped an adorable pic with the birthday girl.

"Unforgettable night," Eva captioned the photo.

Cara, 23, also took to Instagram to share some highlights from the night, like this artsy close-up of Jenner's bum. "Piece of CaKe," she wrote.

WATCH: Khloe Kardashian Shows Off Booty in Sexy Swimsuit

"Face off," Cara captioned another photo of the masked beauties.