a celestial mix-up, the soul of the principal of Lilliard Music School is "double-booked" for both Heaven and Hell. Refusing to depart until his beloved school is saved from a corrupt new chairman, the principal strikes a deal: he will surrender his soul to whichever side—Angels or Demons—helps him reclaim the school through their activities as idols. The story follows three humans, three angels, and three demons as they train to become top-tier idols on Earth.