Famous as the lead vocalist of the South Korean boy band U-KISS, he recorded Only One (2010), Neverland (2011), "Tick Tack" (2012), and other popular albums and singles with the group.
He spent his youth playing soccer and, after deciding to pursue a career in music, trained with both Good Entertainment and JYP Entertainment. He made his U-KISS debut in 2006.
Between 2010 and 2015, he attracted an audience of over 600,000 Twitter followers.
He was born and raised in Gyeonggi-do, South Korea. His U-KISS band "family" includes Kevin, AJ, Kiseop, Hoon, and Eli.
He and SS501 leader Kim Hyun-Joong both fronted popular South Korean boy bands.