It served as the final single from her fifth studio album, CRASH .
The phrase "solid paper" isn't a lyric in Charli XCX 's but it likely refers to her long-standing relationship with PAPER Magazine , where she has frequently broken down her music .
You can see all those iconic outfits in action in the official music video here: Charli XCX - Used To Know Me (Official Video) Charli xcx YouTube• Apr 15, 2022
Alternatively, if you're thinking of the song's , it’s famous for a rapid-fire series of "solid" high-fashion looks—including a cheerleader , Marie Antoinette , and a lingerie-clad nun —that Charli used to represent her various pop personas. Key Facts About "Used To Know Me"