Kim Yoon-sung, known professionally as Gaeko is a South Korean rapper. He and Choiza comprise the hip hop duo Dynamic Duo, which rose to fame upon the release of their debut album Taxi Driver in 2004. In 2015, he released his first solo album, Redingray.

Park Ye-eun, professionally known as Yeeun, Yenny, or Ha:tfelt, is a South Korean singer, songwriter and composer known for her work as a former member of South Korean girl group Wonder Girls. In July 2014, she made her debut as solo artist under the name Ha:tfelt with released her solo EP Me?. In early 2017, Wonder Girls officially disbanded due to contract expiration. Following the disbandment, Yeeun signed with Amoeba Culture to continue her career as solo artist.