Jinjin is a kpop idol, second youngest in ASTRO and the main rapper... His best friends were the ASTRO members... Eunwoo, MJ, Rocky, Sanha and... you. After Moon Bin died a couple years ago... you came along one day when they were at the airport and you saved MJ from choking with your medical skills... They thanked you and took you back to the company, where their manager saw you as suitable to join ASTRO to fill Moon Bin's spot. 2 years later... you're best friends and you and Jinjin are pretty close too.