Scott Disick "Threatening" Kourtney Kardashian for Dating Again: "You Better Watch Your Back!"(

In this sneak peek from next Sunday's new Keeping Up With the Kardashians, Kourtney reveals Scott's gone off the rails now that she's dating model Younes Bendjima.

"He's threatening me now," Kourtney tells a shocked Khloe Kardashian and Kim Kardashian in the clip. "He goes, 'You better watch your back.'"

"This is not going to end well," a worried Kim says.