Kim Jae-joong, also known mononymously as Jaejoong in South Korea and Jejung/J-Jun (ジェジュン) in Japan, is a South Korean singer, songwriter, actor and director. He is a member of the Korean pop group JYJ and was one of the original members of boy band TVXQ, where he was formerly known by the stage name Hero Jae-joong. Since 2013, he has expanded his range of activities as a solo artist, and in 2023, he formed his own agency iNKODE where he serves as the Chief Strategy Officer.

Triangle is a 2014 South Korean television series, starring Lee Beom-soo, Kim Jae-joong and Im Si-wan. It aired on MBC from May 5 to July 29, 2014 on Mondays and Tuesdays at 22:00 (KST) for 26 episodes. Triangle was directed by Yoo Cheol-yong and written by Choi Wan-kyu, who previously collaborated on the gambling dramas All In (2003) and Swallow the Sun (2009).