Lightsum (Korean: 라잇썸; RR: Raitsseom; MR: Raitssŏm, commonly stylized as LIGHTSUM), is a South Korean girl group formed by Cube Entertainment. The group is composed of eight members: Sangah, Chowon, Nayoung, Hina, Juhyeon, Yujeong, Huiyeon, and Jian. The group debuted on June 10, 2021 with the release of their debut single album, Vanilla.