Now, he's using Instagram to do just that.
"Omg who is this!!" the Bieb captioned the pic, which quickly earned more than one million likes.
By the next day, fans hoping to help their pal find his mystery girl had directed the singer to to account for Cindy Kimberly, whose Instagram handle @wolfiecindy has more than 104,000 followers.
No word on whether Justin, who's posted multiple photos of his ex, Selena Gomez, in recent weeks, has followed up on intel about the young woman's identity.
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