Kourtney Kardashian Shares a Nude Backside Photo Amid Bieber Romance

Gettin’ cheeky! Kourtney Kardashian shared a racy black-and-white photo on Instagram of herself wearing nothing but her birthday suit on Wednesday, December 16 — just days after Us Weekly confirmed that she and heartthrob Justin Bieber are hooking up.

The image, which is part of a nude portrait series by photographer Brian Bowen Smith, simply shows the 36-year-old reality star’s toned behind, her long flowing hair, and just a hint of side-boob.

The mother of three used a dark moon emoji to caption the artistic shot.

Us Weekly exclusively revealed that Kardashian and Bieber, 21, have been seeing each other in secret for the last four months.

“Justin and Kourtney have been hooking up since late August, early September,” a source told Us.

Added another source, the “Sorry” singer has already “bragged” to his friends about his tryst with the mom of three.

“Justin started hanging out with Kourtney alone because she started going out more,” the second source said.

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Kardashian’s ex Scott Disick, meanwhile, hasn’t said anything about the new coupling, in light of the fact that he was the one who was caught cheating on Kardashian with his ex-girlfriend Chloe Bartoli back in July.

“Scott feels she’s doing this to get back at him and get revenge,” an insider told Us. “He feels he has to take it and can’t say anything after all he did to her, but he thinks it’s dumb and immature.”

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In October, Disick, 32, seemed to be regretting his actions, and posted another outtake from Kardashian’s nude photo shoot to his Instagram account.

“Now that’s 1 hot mama,” he captioned the shot, in which a naked Kardashian lay down facing away from the camera.

He and the reality star are parents to Mason, 6, Penelope, 3, and Reign, 12 months.

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