Diva on set!

After Scott Disick arrives at his Men's Fitness shoot sans underwear, he sends his assistant, Dale, to fetch him a fresh pair.

With Dale out shopping, Kourtney Kardashian's longtime beau decides to flirt with the wardrobe assistants. "I like that you can see my penis through my pants," Disick chuckles while trying on clothes.

But when Dale returns with a pair of boxer-briefs, Disick's infamous temper flares.

"I wanted boxers," Disick, 27, fumes.

"I know, but that's all they had in medium," Dale explains.

"Dale, do your job," Disick snorts. "Do I work for you or do you work for me?

Kourtney and Kim Take New York airs Sunday at 10 p.m. (EST) on E!.