Scott Disick's former manager is ripping into "the Lord's" recent bad boy behavior and Breaking Celebrity News has learned he's warning Kourtney Kardashian's baby daddy to watch his next move!

During an in depth interview on the Allegedly podcast with Theo Von & Matthew Cole Weiss, reality producer and ex Sons of Hollywood star David Weintraub had some harsh words for Disick.

"I love Scott to death, but fame and money changed who he is. He's got to remember who he is and where he comes from," he said. "And where he comes from is me and Sean Stewart's couch."

As Breaking Celebrity News previously reported, Disick was spotted canoodling with a bevy of beauties in Miami this week, none of whom were Kourtney.

"He always felt like he was entitled, but like you've really got to have talent," Weintraub said of his former couch-mate. "When you're lucky to be famous, and you're lucky to make money, it's different."

Weintraub takes credit for introducing Disick to Kourtney during a party. He also says he made Disick MILLIONS of dollars in personal and professional deals, and is still owed several hundred thousand dollars in fees and other expenses.

"I brought him tons and tons of deals that he f****d up," Weintraub said. "F****d up my relationships with people because either he didn't perform, or he wanted too much money, or he was a d**k, or he did a deal and then f****d it off, and everybody has egg on their face."

Disick jetted to Costa Rica to vacation with Kourtney this week, but their happy family reunion was short-lived. Instead of heading home to LA following the trip, the star flew Miami to hook up with SEVERAL much younger women.

In photos obtained by Breaking Celebrity News, Disick is seen cozying up to numerous bikini-clad babes in Miami, drinking, smoking, and even groping some of them.

Weintraub warned his former client to watch his back.

"He actually thinks he's some big superstar who has talent and does stuff," Weintraub said. "When you get a lot of fame for not really doing anything, or you get a lot of money for not really doing anything, you have to remember how you got there. Don't change as a person."