Ryu Sung-min (Hangul: 류성민; born February 28, 1993), better known by his stage name C Jamm (Hangul: 씨잼), is a South Korean rapper. He released his debut album, Good Boy Doing Bad Things on July 17, 2015. He is the runner-up of Show Me the Money 5, behind the winner, his childhood friend, BewhY.