Charli xcx joins Billie Eilish for the live debut of her “Guess” remix in LA

Billie Eilish’s latest concert got the brat Treatment.

On Tuesday, December 17, Charli xcx made a surprise appearance at the “Birds of a Feather” hitmaker’s concert in Los Angeles at the Kia Forum.

Just one day before Eilish’s 23rd birthday, the two celebrated with the live debut of their “Guess” remix from the “Apple” musician’s acclaimed album Brat and It’s the same but There’s Three More Songs Also It’s not.

During the set, the two were enveloped in green laser beams that bounced across the stage, lighting up the audience.

As Charli, 32, and Eilish, 23, danced, the crowd chanted the lyrics: “Don’t have to guess the color of your underwear/I already know what you’re up to down there/It’s this black lace pair with the little bows/those.” that I picked out for you in Tokyo,”

The “360” musician also shared her excitement about her set on Instagram with a video of her set and a tribute to her birthday.

“I love you Billieeeeee and HBD!!! <3,” Charli wrote on the social media platform.

In August, Charli and Eilish released their “Guess” remix with an accompanying music video.

In the Aiden Zamiri-directed visual, Charli is at a house party where people are drinking and dancing as they begin to strip down to their underwear. Eilish then breaks into the house with a bulldozer to sing her part of the song.

They then end up outside surrounded by industrial buildings as it starts raining bras and underwear. (According to a press release, all bras and underwear used in the music video were donated to I Support the Girls.)

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During the song, Eilish adds a clever — and flirty — nod in the chorus.

“I wanna taste it, bite it, lick it, spit it out/Pull it to the side and come all the way in with it/Kiss it, bite it, can I fit in there?/Charli likes boys but she knows I’d hit.” ” it/Charli, call me when you’re there,” Eilish, who is open about her bisexuality, sings on the track.

“Guess” was originally released as part of Brat and it’s the same thing, but there are three more songs, so not in June.