Source: http://www.crazydaysandnights.net

This rarely seen reality star from an A list reality family was getting laughed at when he would invite Instagram models to his house to have se-x, so he lost a bunch of weight.

Rob Kardashian

Rob Kardashian Sober and Slimmer … At Kim’s 39th Bday

Rob Kardashian’s been using his time out of the public eye to focus on his health and drop some pounds … and a lot of it’s thanks to saying no to alcohol.

The Kardashian bro was spotted in Kim’s Instagram Story from her birthday celebration Monday night, clearly looking a lot leaner than he used to.

Sources close to Rob tell TMZ … he quit drinking recently and has been focusing on making better diet choices — including cutting down on fast food. We’re told he’s also exercising on the reg and playing a lot of basketball to get in shape.

All of this combined has led to him shedding a lot of weight — our sources say in the ballpark of 20 lbs. … maybe more compared to a couple years ago. – Source

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