Kardashian, 37, turned heads during the night out in a sheer lace La Perla top, which exposed her nipples. The "Love Yourself" singer, 22, meanwhile, went casual in a gray hoodie and baseball cap.
Despite the run-in, the pair arrived separately. A source tells Us Weekly that Bieber was with a group of friends — including former One Directioner Liam Payne — at the live music venue for about two hours. The Keeping Up With the Kardashians star arrived second and stayed for only about 15 minutes.
The reunion didn't end there, however. Kardashian and Bieber would later meet up at hot spot Delilah before saying goodbye at 2 a.m. "They were just there as friends, with friends and and it was not romantic," the source tells Us.
As Us Weekly exclusively revealed, things heated up between Kardashian and Bieber after the reality star ended her nine-year relationship with Scott Disick in the summer of 2015, and they got together in "late August, early September" of that year.
"Every time Kourtney and Justin are together they’re extremely flirtatious," the source said at the time. "They text each other all the time." More recently, Kardashian — who continues to coparent with Disick — hooked up with a 23-year-old model named Younes Bendjima.
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