Rob Kardashian Blames 40-Pound Weight Gain on Ex Rita Ora

It sounds like Rob Kardashian needs a lesson in responsibility. The 25-year-old admitted on Sunday’s episode of “Kourtney and Kim Take Miami” that he’s packed on the pounds recently … and claims it’s all ex-girlfriend Rita Ora’s fault.

“All I did was waste a lot of money and gain 40 pounds,” he tells his sisters over dinner, which ironically consisted of pizza and pasta. “I need to focus on me. That’s all I wanna be about."

Kardashian dated the British songstress for about a year, but according to sister Khloe the relationship was rather “weird” since he wasn’t allowed to admit they were actually together because Ora wanted to keep up a single-girl image for the sake of her career.

“I think Rob got kind of depressed,” Khloe said on camera.

Back in December, Kardashian gained attention for bashing the 22-year-old pop star after their breakup with a series of tweets claiming he had gotten her pregnant and that she had cheated on him with “nearly 20 dudes.”

He explained why he posted the mean-spirited comments on Sunday’s episode. “I posted what I posted to stop myself from taking her back,” said Rob, adding he wanted “to make her hate me.”

Well, that part worked, but there’s still the pesky issue of those unwanted 40 pounds.

A year and a half ago the reality star did manage to drop some weight when he competed on “Dancing With the Stars.”

"You probably wouldn't know, but I'm the most insecure and overweight I've ever been," he said on the show in August of 2011, when the 5’10” Kardashian’s weight topped 200 pounds.

Without a dance competition show to help him, the sock designer may have to actually resort to proper diet and frequent exercise … and it seems like he's already on the right track, tweeting out a photo of some grapefruit and a small omelet on Thursday morning, and writing: "Another fat boy breakfast. Let's go! 5 mile run next. 50 pounds gots to go!"

If it doesn't work, we're sure he'll find someone else to blame.

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