A foreign rock band (Aurora). Jioh discovered them by chance during school and they became his muse. He then pursued music, becoming a skilled composer. However, Aurora disappeared, unable to survive the competitive music market. Then, a mysterious man, Seongyu, appears before Jioh, who can't forget the voice of Aurora's vocalist. Their first meeting is suspicious, but Jioh learns from his close friend, Heeseop, the shocking news that Seongyu's voice resembles Aurora's vocalist… "Hyung, please just sing once!" "No." Just one line… what's so hard about that?!