Lee Chang Sub (이창섭), better known by his homonymous name Changsub (창섭), is a South Korean singer and actor. He is the main vocalist of the South Korean group BtoB. Changsub was born on February 26, 1991 in Suwon, Gyeonggi, South Korea. He studied practical music at Howon University. Changsub debuted as a BtoB vocalist in 2012. He also participated in the songwriting of some BtoB songs, including “Last Day”, “Killing Me” and “Melody”.