I. Personal Life
Sungjae was born Yook Sungjae (육성재) on May 2, 1995 in Yongin, Gyeonggi Province. His grandfather was the first one to introduce red carp in South Korea. He briefly studied abroad in English and the Philippines as a child. He attended Hanlim Multi Art School and graduated in 2014.
On May 11, 2020, Sungjae announced via Instagram that he would be enlisting for his mandatory military service. He is currently serving as a member of the military band and will be discharged in November 2021.
Sungjae debuted as a vocalist for BtoB n March 21, 2012. He also participated in the subunit BtoB Blue. He briefly served as BtoB's leader after Minhyuk's enlistment.
IIII. Solo Activities
In March 2012, Sungjae was chosen as co-host of SBS MTV's The Show alongside group member Minhyuk.
In 2013, Sungjae made his acting debut in the drama Monstar as part of the supporting cast. Sungjae acted as Arnold, a member of boy idol group 'Men In Black'. He appeared in 4 episodes in total.
In 2014, Sungjae appeared in the television series Reply 1994 as Sungjoon. In July 2014, he was cast as a presenter for the program, A Song For You alongside Kangin of Super Junior and Amber of f(x). He also participated in the program Hitmaker season 1, presented by South Korean producer duo Jeong Hyeong-don and Defconn and became part of the program's project unit group, Big Byung, together with Got7's Jackson and VIXX members, N and Hyuk. The group then releases two singles: "Stress Come On" and "Ojingeo Doenjang". The same year, he received his first main acting role in Plus Nine Boys. He then joined the reality-variety program Real Men from 2014–2015.
Sungjae achieved his breakthrough when he landed a leading role in the teen drama Who Are You: School 2015 After the series ended, he experienced a rise in popularity and landed several endorsement deals. Sungjae then starred in the horror mystery series The Village: Achiara's Secret alongside in 2015. He received the "New Star award" for his performance in The Village: Achiara's Secret and won "Best Couple award" with Kim So-hyun for Who Are You: School 2015.
Sungjae was paired up with Red Velvet's Joy in the fourth season of reality show We Got Married. The couple went on to release a duet titled "Young Love", with the pair contributing to the lyric composition of the song with the help of his bandmate BTOB's Im Hyun-sik as the producer. At the 2015 MBC Entertainment Awards, Sungjae received the "Best Couple award" alongside Joy and the "Best Male Rookie (Variety) award". In September 2015, Sungjae became one of the main hosts of the music-program Inkigayo alongside GOT7's Jackson Wang and actress Ki Yoojng. He left the show in May 2016.
From 2016 to 2017, Sungjae starred in the hit fantasy-romance drama Guardian: The Lonely and Great God. In August 2017, he participated in the digital single project, Piece of BtoB. He released the songs "Say It" and "Paradise", the latter having been personally composed and written by himself, on August 30. In late 2017, he joined the cast of the reality show, Master in the House.
On December 29, 2017, Cube Entertainment announced that Yook suffered a back injury and would be receiving treatment at the hospital. He had symptoms of lumbar disc herniation reportedly worsened during the concert 2017 BtoB Time - Our Concert.
Sungjae appeared in Mystic Pop-up Bar, a JTBC drama based on a popular webtoon of the same name in early 2020. On February 18, he left the cast of Master in the House after two years for the preparation of his mandatory military service. Sungjae released his first solo album since debut Yook O'Clock on March 2, 2020 which consisted of six songs from 3X2=6 and lead single "Come with the Wind".
|Tell Me (Piece of BtoB, Vol. 6)||August 30, 2017|
|Yook O'Clock||March 2, 2020|
|2013||The Heirs||Himself (cameo)||SBS|
|2013||Replay 1994||Sung Joon||tvN|
|2014||Plus Nine Boys||Kang Mingu||tvN|
|2015||Who Are You: School 2015||Gong Taekwang||KBS2|
|2015||The Village: Achiara's Secret||Park Woojae||SBS|
|2016-17||Guardian: The Lonely and Great God||Yoo Deok-hwa||tvN|
|2018||Dae Jang Geum is Watching||Oh Sungjae (cameo)||MBC|
|2020||Mystic Pop-up Bar||Han Kangbae||JTBC|
IVII. Variety Shows
|2012||The Show||Main Host||SBS MTV|
|2014||Real Men||Cast Member||MBC|
|2014||A Song For You||Main Host||KBS|
|2015||Invisible Man||Cast Member||KBS|
|2015||King of Masked Singer||Contestant||MBC|
|2015-16||We Got Married||Cast Member (with Joy)||MBC|
|2016||Duet Song Festival||Contestant||MBC|
|2017||Celebrity Bromance||Cast Member||MBigTV|
|2017||Law of the Jungle in Sumatra||Cast Member||SBS|
|2017-20||Master in the House||Cast Member||SBS|
|2019||Lovely 95s||Cast Member||Cube TV|
|2015||KBS Drama Awards||Best Couple (with Kim Sohyun)||Who Are You: School 2015|
|2015||MBC Entertainment Awards||Best Male Newcomer Award (Variety)||We Got Married|
|2015||MBC Entertainment Awards||Best Couple Award (with Joy)||We Got Married|
|2015||SBS Drama Awards||New Star Award||The Village: Achiara's Secret|
|2017||Korea Cable TV Awards||Rising Star Awards||Guardian: The Lonely and Great God|
|2017||10th Korea Drama Awards||Best New Actor||Guardian: The Lonely and Great God|
|2017||10th Korea Drama Awards||Star of the Year Award||Guardian: The Lonely and Great God|
|2017||Korea's First Brand Awards||Male Acting Idol||-|
|2018||MTN Braodcast Advertising Festival||CF Male Star Award||-|
|2018||SBS Entertainment Awards||Excelelnt Award Variety Department||Master in the House|
|2019||SBS Entertainment Awards||SNS Star Award||Master in the House|