Kim Ji-yeon, known professionally as Kei, is a South Korean singer and musical actress. She rose to fame as a member of South Korean girl group Lovelyz in November 2014. Kei officially made her solo debut with the EP, Over and Over on October 8, 2019. On November 16, 2021, she left Woollim Entertainment, although she remains as a member of Lovelyz. She joined Palm Tree Island in January 2022 to focus on her musical career, before moving to A2Z Entertainment later that year. In 2023, Kei participated in Mnet reality competition show Queendom Puzzle, debuting with the resulting project supergroup El7z Up in September of that year.