 However, Sechs Kies suddenly disbanded in 2000 after finishing their fourth album promotion.After SechsKies disbanded, Sung-hoon was the second member from Sechs Kies to begin a solo career mainly on R&B and ballad.In 2001, he released first album""비상(Bee Sang)"" with title song "고백(Confessions)" and most of the Sechs Kies members chorus "1년 되는 날 (1st Anniversary)".