There are several artists with the name Cool: 1) - Cool is a Korean ballad/pop group that first appeared in 1994. The main members include Kim Sung Soo (김성수) as the male rapper of the group and known for being "goofy", Yuri (유리) as female vocalist, and Lee Jae Hoon (이재훈) as the driving force behind the group's music and lead vocalist. Former members include Yoo Chae Young (유채영), who was the original female vocalist, but left after the first album and has since made a career in acting, and Choi Joon Myoung (최준명). The group has produced seventeen albums .