Days after joining her onstage in Miami, the singer crashed Grande's L.A. concert to perform several songs.
Justin Bieber made another surprise appearance at an Ariana Grande show!
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The singer shocked fans by joining the "Problem" singer onstage at The Forum in Inglewood on Wednesday. The 21-year-old pop stars sang Grande's song with The Weeknd "Love Me Harder" together before Bieber took the stage solo to perform his track "Where Are You Now."
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Grande then returned for a duet performance of Bieber's hit single "As Long As You Love Me."
A few times the two seemed to get a little bit flirty, with Bieber putting his arms around Grande's waist, which made the fans in the crowd absolutely freak out!
This marks the second time Bieber has taken the stage on Grande's recent tour. He also made a surprise appearance at her Miami concert just two weeks ago.
WATCH: Justin Bieber -- Selena Gomez Inspired A Lot Of Music On My New Album
While he performing with his pal Grande, Bieber has said that his new music is heavily influenced by his relationship with ex-girlfriend Selena Gomez. See more in the video below.