LIL FANTASY vol.1 is Chaeyoung's debut solo studio album, released September 12, 2025 through JYP Entertainment and Republic Records. She is the fourth TWICE member to debut solo — following Nayeon (2022), Jihyo (2023), and Tzuyu (2024) — and notably the first to launch with a full-length album rather than a mini. Chaeyoung began developing the project as far back as late 2022 and has composition, arrangement, and lyric credits across all ten tracks, with sole writing credit on three of them. The album spans ten tracks: "Avocado" (feat. Gliiico), "Band-Aid," "Shoot (Firecracker)," "Girl," "Ribbons" (feat. Sumin & Jibin of Y2K92), "Downpour" (with Kai of Gliiico), "BF," "그림자 놀이" (Shadow Play), "내 기타" (My Guitar), and "Lonely Doll Waltz" — the last being a CD-only bonus exclusive to physical copies. The sound spans jazz-disco ("Shoot"), dream pop ("Downpour"), R&B ("Band-Aid"), and guitar-driven indie pop ("Girl"). "Ribbons," written entirely by female artists, evolved from three separate pieces that Chaeyoung, Sumin, and Jibin each wrote independently about hardships they overcame. "Shadow Play" addresses the experience of concealing her identity to avoid recognition in public — one of the album's most personal moments. Physically the album comes in eight versions. Glimmer and Murmur are the standard editions, each containing a 96-page photobook, 4 photocards (random 4/15), interview card (1/3), printed photo (1/3), folded poster (1/3), key tag, lyric map, and envelope — plus pin button and poster as pre-order exclusives. Sparkle is a compact edition with a 24-page photobook, photocard, polaroid photocard, and sticker. Canvas is the most distinct version — rather than a traditional photobook it includes a 68-page coloring book, a five-piece colored pencil set, a 16-page lyric book, photocard (1/3), and bookmark (1/3). Three vinyl editions were also released: Target-exclusive Avocado, the standard Avocado Pit, and TWICE Store-exclusive Downpour. A Platform Nemo digital version rounds out the lineup. Commercially, the album debuted at number 38 on the Billboard 200 and topped the Billboard Emerging Artists chart. It appeared on Rolling Stone's 100 Best Albums of 2025 at number 86, was named one of Billboard's 25 Best K-Pop Albums of 2025, and was cited by the Recording Academy as one of September 2025's must-hear releases.