Kourtney romancing Justin Bieber to get back at Scott

Kourtney Kardashian is on the rebound.

After splitting from Scott Disick earlier this year, the 36-year-old reality star was spotted getting cozy with Justin Bieber all over Los Angeles on Saturday night.

The couple partied together at The Nice Guy in West Hollywood, where a spy said Kardashian excitedly watched as Bieber, 21, performed two of his hits.

“Justin and Kourtney were nearly inseparable,” the source told Page Six. “They were smoking on the patio together and were super touchy-feely.”

After leaving the upscale eatery together, the affectionate pair continued celebrating at Blind Dragon, but avoided exiting the Asian-themed lounge at the same time.

“Kourtney left around 12:45 a.m., but Justin stayed until 1:30 a.m.,” said the insider.

The source revealed that the pair eventually made it to Bieber’s hotel room at the Montage, where the mother of three was spotted leaving at 4 a.m.

In an apparent jab at “Lord Disick,” a nickname that Disick, 32, created for himself, Bieber posted a photo to Instagram Sunday of himself straddling a mystery woman on the hood of an Audi sports car alongside the cryptic caption, “Lord knows.”

“Scott hates it that Bieber is the younger, hotter and richer version of him — in his eyes — and seeing him with Kourtney pisses him off even more,” said the insider. “Kourtney knows it upsets him, so when Scott flaunts being out with other girls, she hangs out with Justin to get back at him.”

But a source close to Kardashian says the reality star and singer are “just friends.”

“[Justin] always has 20 people with him at the hotel,” they said.

Requests for comment from reps for Bieber, Disick and Kardashian were not immediately returned.

With additional reporting by Carlos Greer