"It's just one of those things where it makes Kourtney feel good about herself," a source tells PEOPLE
“It’s been a deep flirtation for months. He’s obviously close to the family, and Kris [Jenner] is obsessed with him,” the source says. “It’s just one of those things where it makes Kourtney feel good about herself. It’s not serious at all. This young guy is into her, he thinks she’s hot and she’s older. She just wants to have fun.”
The source adds that even when Kardashian and Bieber are in the same room, they send each other flirtatious texts, and when they’re together, “they’re cuddly and huggy.”
A second source adds that the pair have been “hooking up” for several months.
The singer, 21, and the Keeping Up with the Kardashians star, 36, were spotted being “super touchy feely,” at the Nice Guy in West Hollywood on Friday, sparking rumors of a romance.
“They all think it’s kind of funny. There’s no ill will at all,” says the source.
Bieber and the Kardashian-Jenner family have a history together, with the singer celebrating Jenner’s birthday with her and her family at The Nice Guy last month.
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Bieber has also palled around with the family in the past, posting a photo of himself in May swimming in a pool with Kardashian’s son Mason, 6.
“Mason is as cool as a fan,” he captioned the photo.