Justin Bieber serenaded a newly-engaged couple outside The Grove in Hollywood last week.

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According to TMZ, the singer did an impromptu performance of Boyz II Men's "I'll Make Love to You" after a man asked him to sing something for his new fiancée.

Bieber even invited the groom-to-be to take over the chorus, cheering him along. What a sweetie!

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How do you rate his performance? Watch below:

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