Billie Eilish is having a Brat summer.

The nine-time Grammy winner hopped on a remix of Charli XCX’sBrat bonus track “Guess,” as well as the music video for the NSFW track.

In the visuals, released on Aug. 1, colorful underwear fly across the screen as Charli lets loose amongst a group of scantily clad dancers. As she sings about her own pair of briefs, the 31-year-old references Billie’s 2024 track “Lunch,” an equally steamy song suspected to be about oral sex.