Billie Eilish is known for her vocals. One fan, however, recently gave her a run for her money at her own concert.

In a video shared to TikTok by @thefamousmikbar, a fan in the crowd can be heard singing along to — or over, rather — Eilish during one of her concert stops.

"To the person who thinks you can out sing Billie and ruined all my [concert] videos," text placed over the footage reads.

The video shows Eilish performing on stage as a fan off screen, but located somewhere near the person recording, belts loudly and performs their own special vocal runs as the pop star performs on stage.

"[You're] not the main character," the clip is captioned. Watch below:

The singing fan drew criticism from many people in the TikTok user's comments section.

"Can’t stand people like that at concerts," one user wrote.

"She totally thought Billie would hear her and pass her the mic and she’d have her moment," another speculated.

"I don’t know how you put up with that," someone else commented.

Others came to the impassioned singing fan's defense.

"It's a concert," one person wrote, while another commented, "I kinda live for it."

"She sings good tho," someone else observed.

Eilish is currently gearing up for a special livestream of her Happier Than Ever: The World Tour event. The event will stream exclusively on Apple Music Friday (Sept. 30) at 10PM EST.

The event is set to include songs from Eilish's most recent album, Happier Than Ever, as well as fan-favorite singles including “Bad Guy,” “Bury a Friend,” “Ocean Eyes” and more.

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