Justin Bieber jumps on the piano to sing to girl in bar in LA

Justin Bieber, 21, surprised a woman celebrating her big night at The Nice Guy in Los Angeles on Monday with an intimate performance.

The singer jumped on the piano and sung a couple of his hits and covered Apologize, according toTMZ.

TMZ reports the star dedicated a song to the birthday girl then bought all of her friends shots of tequila.

A video posted to TMZ shows him singing the lyrics: ‘What did I do to deserve your love baby. What did I do. What did I do. What did I do.’

As he was spotted leaving the West Hollywood hot spot the pop star was dressed casually in a grey beanie, light blue denim jacket, white shirt and tan pants. 

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