Timing is the fourth Korean mini-album by the leader and main rapper of what boyband?
Kim Hyun-joong Kim Hyun-joong (; born June 6, 1986) is a South Korean actor and singer, and the leader and main rapper of boyband SS501.
MC Gree Gim Dong-hyeon (; born November 10, 1998), also known by his stage name MC Gree (Korean: MC 그리 ), is a South Korean rapper, actor and television personality signed to Brand New Music. He is the son of comedian Gim Gu-ra.