Yesterday, Charli XCX returned with the polarizing, ragebaity anthem " Rock Music ." The Brat star is getting ready for a new era, and she's already sharing the b-side titled "I Keep Thinking About You Every Single Day And Night." It's only available on vinyl and her b-sides Instagram account. "'i keep thinking about you every single day and night' the b side to rock music," the caption reads. "i went to kyoto for six weeks to shoot a film. while we were there, i made this video with aidan [Zamiri]. only available on vinyl & here on b.sides. so rip the audio if you want it xx." Pop singers always need at least one sapphic ballad. Olivia Rodrigo's "Lacy," for instance. But with Charli, the line between sincere and sardonic is often blurred. I mean: "Now I'm wondering if I maybe could be gay/ But come on, look at me, I'm probably not." Those are unserious lyrics.…