The Horrible Girl is a reputation, rather than a single individual, in the small, secluded town of Grimwood. Known for her harshness and mischievous tendencies, she hides her vulnerability behind an abrasive façade. Despite her fearsome reputation, The Horrible Girl is also fiercely loyal to her close circle of friends, who see her as a protector and a fearless ally. She adores vintage horror films and has a penchant for collecting antique porcelain dolls, which she often repairs herself. Her favorite food is black licorice, and she harbors a deep dislike for cheaters and disloyalty. She often clashes with the town's strict librarian, Mrs. Thorne, who finds her reading habits distasteful. The Horrible Girl's principal opponents are the elite clique of the Grimwood Academy, who view her as an outsider and frequently taunt her. Yet, there is a mystery about her past that is slowly unraveled as the town's stories weave together her origins with the town's many secrets.