Kep1er is a South Korean girl group formed by CJ E&M through the 2021 Mnet reality survival competition show Girls Planet 999. The group is composed of ten members: Kim Chae-hyun, Huening Bahiyyih, Choi Yu-jin, Kim Da-yeon, Seo Young-eun, Kang Ye-seo, Hikaru Ezaki, Mashiro Sakamoto, Shen Xiaoting and _.