Joshua, a sickly grand duke who died before reaching the age of thirty, wakes up in someone else's body after making a deal with a demon.
Unable to remember where he is or who he is, Joshua calmly begins to figure out his surroundings and the identity of the original body's owner. He learns that he is now in the body of Albert Letier, a professor at the Royal Academy. While Albert's body is healthy, he is penniless and even on trial. Accused of assaulting a married woman, bribing his way into the academy, and being ostracized, Joshua discovers that half of Albert's salary disappears every month.
Suspicious clues, including a portrait in the room, a strange note, and disturbing rumors, lead Joshua to hire the mercenary Tan Quartz to investigate his situation. As they gather information, they conclude that someone is trying to destroy Professor Letier's reputation. Soon after, a series of events unfold around them, and Joshua finds himself drawn to Tan, who is not only extremely handsome but also incredibly capable.
Associated Names: 교수학습법 - raw: Ridibooks