H1-KEY (하이키) is a girl group under Grandline Group. They debuted on January 5, 2022 with the release of the digital single "Athletic Girl". The group currently consists of 4 members: Seoi (서이), Riina (리이나), Hwiseo (휘서), and Yel (옐). On May 24, 2022 it was announced that former member Sitala (시탈라) left the group due to personal reasons. On June 6, 2022 it was announced Hwiseo was added to the group. The group had their first comeback on July 6