The captionless black-and-white photograph shows Aniston, 46, smirking on the left while Bieber, 21, makes a surprised face on the right-hand side of the picture.
But while the Bieber-Anistion combination is one we weren't expecting to see crop up on our social media feeds, the pair do have one important person in common: Selena Gomez.
Bieber and Gomez are of course exes, while Aniston and Gomez have become besties in recent months, after being introduced by their mutual management team.
"We’ve made pizzas at her house," Selena said during a radio interview with KTU recently. "She’s very cool and very sweet. She kind of gives me a lot of, like, maternal advice," she added.
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