Kei (케이) – A New Day
Track 01 from Single '손해 보기 싫어서 OST Part 6'
Kei (케이) – 스며드는 중
Track 01 from Single '나는 대놓고 신데렐라를 꿈꾼다 OST Part 1'
Kei (케이) – 안녕
Track 05 from EP "너의 시간 속으로 OST"
Release Date: 2023.09.08
나나 (NANA), 수윤, 연희, 우연 (WOOYEON), 유키, 지한 (Weeekly), Kei (케이) – Billionaire
Track 01 from Single "퀸덤퍼즐 FINAL"
Release Date: 2023.08.16
리이나 (하이키), 시로마 미루, 수윤, 이수진 (Weeekly), 우연 (WOOYEON), 지원, Kei (케이) – PUZZLIN′
Track 01 from Single "퀸덤퍼즐 SEMI FINAL"
Release Date: 2023.08.09
나나 (NANA), 상아, 수윤, 예은, 우연 (WOOYEON), Kei (케이) – BAD BLOOD
Track 01 from EP "퀸덤퍼즐 ALL-ROUNDER BATTLE 2"
Release Date: 2023.07.19
Kei (케이) – 썸머러브블루스 (Summer Love Blues)
Track 01 from Single "썸머, 러브머신 블루스 OST (O′PENing)"
Release Date: 2023.07.16
Kei (케이) – 바람의 노래
Track 01 from Single "구미호뎐 1938 OST Part 4"
Release Date: 2023.05.28
Kei (케이) – 연가(戀歌)
Track 01 from Single "구미호뎐 1938 OST Part 2"
Release Date: 2023.05.14
Kei (케이) – YOU KNOW ME BETTER (ACOUSTIC)
Track 20 from Album "오아시스 OST"
Release Date: 2023.05.01
Kei (케이) – YOU KNOW ME BETTER
Track 19 from Album "오아시스 OST"
Release Date: 2023.05.01
Kei (케이) – YOU KNOW ME BETTER (ACOUSTIC)
Track 02 from Single "오아시스 OST Part 5"
Release Date: 2023.04.11
Kei (케이) – YOU KNOW ME BETTER
Track 01 from Single "오아시스 OST Part 5"
Release Date: 2023.04.11