Junhyung was born in Seoul, South Korea. He changed his birth name Yong Jae Soon (Hangul: 용재순) to his current name when he was in 6th grade. He was once a member of the boyband Xing along with Kevin Woo, former member of U-KISS, and was known as Poppin' Dragon when he was promoting with them. He is a member of South Korean boy group Highlight (Beast). He was featured in various singles as a rapper for artists such as former lablemate Hyuna's "Change" and G.NA's "Kkeojyeo Julge Jar Sara" (꺼져 줄게 잘 살아, lit. I'll Back Off So You Can Live Better), Young Jee's "Crazy, that's what love is", Navi's "Go Again" and Wheesung's "Words That Freeze My Heart".