Yook Sung-jae (Korean: 육성재; Hanja: 陸星材) is a South Korean singer, songwriter, actor, model, host and entertainer. He is a member of the boy group BtoB and its sub-group, BtoB Blue. Aside from his group's activities, Yook has acted in television dramas and has appeared in several reality shows.
Yook released his debut solo album, Yook O'Clock, on March 2, 2020.
