Lee-U (이유 (born March 20, 1990 (21), real name Lee Seung Hyun (이승현, is the son of Sul Woon Do, a famous trot singer in Korea. He is nicknamed "the Reason of F.Cuz", suggesting that with his talented singing ability, inherited from his father, he has made F.Cuz exist. He is the main vocalist of the group.
, is the son of Sul Woon Do, a famous trot singer in Korea. He is nicknamed "the Reason of F.Cuz", suggesting that with his talented singing ability, inherited from his father, he has made F.Cuz exist. He is the main vocalist of the group.
