Charli XCX recently responded to claims that “brat summer” is “over” by posting, “Oh? see u next week:).” Now she’s giving more of a tease about what she meant by that.

The "Apple" singer has posted a black-and-white photo of a woman in lingerie that's cut off above the bra line. She has her back turned toward the camera; the words "lower back tattoo" are written on, yes, her lower back.

Also in the photo is a person of indeterminate gender standing next to the woman, cut off at the chest so you can't see their face. They're wearing low-slung pants and a shirt they're pulling up to reveal the tops of what look like three pairs of boxer shorts.

On the far right side of the photo is a label that reads "charlie xcx guess featuring..." and then a bunch of blank spaces, like in the game Hangman. "Guess" is the name of a song on the deluxe version of Charli's album brat.

Charli wrote in the caption, "Guess ?"

Many fans believe the person standing next to the woman in the photo is Billie Eilish, based on a side-by-side comparison of the person's left hand with Billie's left hand: They appear to be wearing the same rings on their index and fourth fingers.

Another person points out that the number of blank spaces matches the number of letters in the name "Billie Eilish."

Fans are, predictably, losing their minds over the prospect of the two powerhouses teaming up. We'll just have to stay tuned.

(A previous version of this story, published on 7/31/2024, incorrectly referred to the title of the song. It has been corrected.)

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