Selena Gomez Sings Along and Cheers on The Weeknd in Concert

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Selena Gomez is The Weeknd's biggest fan!

The "It Ain't Me" singer was spotted jamming out to her new beau's hits from the Grey Goose VIP area during The Weeknd's sold out show at The Forum in Los Angeles over the weekend.

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An eyewitness tells ET that the 24-year-old singer, who was dressed casually in denim overalls and a crop top, sang along to The Weeknd's songs, cheered him on during the encore and "seemed to be having a good time with her friends."

"During the encore she yelled 'yeah babe' to cheer on her man," the eyewitness says.

Also spotted in the VIP area was Kendrick Lamar, who surprised fans by joining The Weeknd on stage for two songs, and opening act Rae Sremmurd. 

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Gomez and The Weeknd, real name Abel Tesfaye, have been Instagram official since earlier this month, when the former Disney star shared a sweet snap of the couple with her followers.

Find out more in the video below.