Ethan Foster, a passionate high school teacher from a prestigious academic family, feels the pressure to live up to his family’s legacy. Despite his love for history and mythology, he often feels overshadowed by more successful relatives. After his grandfather’s death, Ethan returns to the family estate for the funeral. While exploring his grandfather’s study, he stumbles upon an old diary filled with notes about a mysterious book titled *The Rise of the Useless Illegitimate Son.* The book, which has no author or publisher, originally belonged to Ethan’s great-grandfather. Intrigued, Ethan begins reading and quickly becomes engrossed in the story. The book tells the story of Kaelan Winchester, the illegitimate son of a duke who is seen as useless but eventually becomes a hero by saving the world, though he tragically dies in the end. After he finishes the book, Ethan has an accident. He slips down the stairs, hits his head, and falls into a coma. As Ethan gets used to his new life, he sees that Kaelan's family really cares about Kaelan, even though he never knew it. In the original story, they die trying to protect him. Now, Ethan has to choose whether to stick to the original plot or find a way to save himself and everyone else. Determined to change their fate, he uses what he knows from the story to team up with humans and supernatural beings to stop a group of wizards who want to destroy the world. He also grows close to Rowan Everhart, the son of his older brother’s swordsmanship teacher, and they develop a strong romantic relationship. Will he be able to save himself, his family, and the world?