A female detective investigates the cause of a high school girl’s death and uncovers a disturbing truth.

When the South Korean Empire's emperor gets sick, the government tries to seek the princess for the crown prince, Lee Shin. Although Shin is already in love with a ballerina, Min Hyorin, Shin has to get married to an ordinary girl, Shin Chaegyeong.

A pitiless demon becomes powerless after getting entangled with an icy heiress, who may hold the key to his lost abilities — and his heart.

Set in the constitutional monarchy in an imaginary South Korea, South Korea's Crown Prince Lee Jae Ha is forced to join the World Officers Competition, WOC, by his brother. There, he meets North Korea's strongest female devil instructor Kim Hang Ah.