File this one under the what the what!? category: Justin Bieber is said to be hooking up with a Kardashian sister -- and it's not Kylie or Kendall Jenner. No, it's the eldest sister of the reality TV clan: Kourtney Kardashian, at least that's the latest from the celebrity rumor mill.
The "Keeping Up With the Kardashians" star, 36, and the "Sorry" singer, 21, a longtime family friend, fueled more reports that they're seeing each other after they both left Hollywood club The Nice Guy on Friday then hung out at karaoke lounge Blind Dragon. After that, Kardashian is said to have made her way to Bieber's hotel, the Montage in Beverly Hills, according to TMZ and Gossip Cop. She reportedly left the hotel at 4 a.m.
A source confirmed to Gossip Cop that the two are "casually hooking up" occasionally and it isn't serious, but they're both having fun.
It also isn't the first time the unexpected pair has gotten together. In October, they both had dinner at the Nice Guy before posting an Instagram selfie wearing 3-D glasses at Universal Studios' Halloween Horror Nights, an "impeccable insider" told the rumor-busting site.
"Justin bragged to friends recently that he has been hooking up with Kourtney Kardashian," an insider told Us Weekly, noting that the petite fashionista attended his American Music Awards after-party at the Nice Guy in November.
Adding fuel to the fire, the reformed pop star posted an Instagram on Sunday featuring himself with a mystery woman that appeared to taunt his legion of fans and possibly the father of Kardashian's three kids, Scott Disick, who also goes by Lord Disick.
Kardashian and Disick split up over the summer after nine years and three kids together. The pair have been off and on as they worked out their problems and recently appeared to be on better terms.
Either way, Bieber is a heck of a rebound guy.
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