Yoon Kye-sang (윤계상) is a South Korean actor and singer. He was born on December 20, 1978, and began his career in 1999 as part of the K-pop boy band g.o.d, then left the group in 2004 to pursue an acting career. Yoon Kye-sang (윤계상) is a South Korean actor and singer. He was born on December 20, 1978, and began his career in 1999 as part of the K-pop boy band g.o.d, then left the group in 2004 to pursue an acting career.