Kourtney K poses nude

Mother of 3 Kourtney K posed nude for a photoshoot with artist Brian Bowen Smith. Younger sister Kylie Jenner was also there to lend her support to Kourtney.

"The whole vibe of the shoot, other than it's going to be nude for the art thing, is that if you're not blown away by your picture, then it means we didn't do it right," Smith tells Kourt.

"The only thing is I feel like my ass like disappeared when I lost weight," Kourtney laughs. "We need to plump it up!"