Duke, whose real name is Bartholomew Maximillian Augustus Fitzgerald Nicholas Ardingly, is the deuteragonist of the novel and Rainy March’s primary love interest. Initially, he exists as a classic noir detective, the hero of a popular book series set in the 1930s. In this role, he is a round but static character, embodying the archetypal traits of his genre: immense charm, intelligence, and a noble heart hidden beneath a suave, unflappable exterior. He is a self-aware parody of the aristocratic detective, using his high status and charisma as tools to solve crimes. His backstory, marked by the tragic loss of his three older brothers, provides the motivation for his work, as he channels his grief into a mission to save others.

Before meeting Rainy, Duke’s existence is confined to the narrative parameters set by his author. Everything changes when the Burner, X, reveals to Duke that he is a fictional character. This revelation transforms him into a dynamic character and a self-aware being. His immediate reaction is an intellectual re-evaluation of his own reality, revealing a characteristic curiosity and open-mindedness. This newfound awareness allows him to manipulate his own story, an ability he uses to save Rainy from X.

Duke’s love for Rainy is the driving force behind his development. He sees her as more substantial than anyone in his own world, telling her, “You’re the realest girl I’ve ever met” (23). This sentiment fuels his desire to break the barriers between the real and fictional worlds, directly engaging with the theme of When Fiction Impacts Reality. As a self-aware character, Duke becomes a rebel like Rainy, actively questioning and defying the Eight Black and Whites. He rejects the notion that he is a second-class citizen simply because he does not physically exist in the real world, and he refuses to have his memory of Rainy erased. His love for her inspires him to literally transcend his own narrative, pulling himself out of his book to be with her in the real world. While his charming and heroic nature remains intact, it is now directed toward a new purpose: solving the mystery of how he and Rainy can be together. He evolves from being a character who follows a predetermined plot to one who actively seeks to write his own story, with Rainy as his partner.

Pops is Rainy’s grandfather and an archetypal mentor figure in her life. As a seasoned and respected Book Witch, he embodies the wisdom and experience of his generation and the unconditional love and support of Rainy. He is a round, static character whose primary motivation is the protection and well-being of his granddaughter. Having already lost his wife Mary and his daughter Ellery, Pops is deeply protective of Rainy, his only remaining family. This protectiveness often manifests as caution, as seen when he initially forbids Rainy from taking the dangerous Duke of Chicago case. He acts as a guardian of both Rainy and the traditions of the Ink and Paper Coven, though his love for his granddaughter ultimately outweighs his adherence to the rules.

Pops’s character serves as the primary catalyst for the central mystery plot. His sudden disappearance at the start of the novel, coupled with a cryptic note and the theft of Rainy’s book, forces Rainy to become a detective in her own life. The clues he leaves behind, such as hiding the key to his desk in the old carriage clock, are deliberately literary, guiding Rainy on a path of discovery that he has carefully orchestrated with Nancy Drew. His actions, while seemingly mysterious, are all part of a plan to help Rainy uncover the truth about her parentage in a way that aligns with the narrative logic of self-discovery required for a fictional character.

Nancy is an important ally and guide to Rainy, initially appearing under the alias of Penny Nichols, a perky and seemingly naive apprentice Book Witch. In her disguise, she acts as a herald, providing Rainy with the necessary tools and information to begin her quest, such as the copy of Pride and Prejudice, and subtle clues about the location of Rainy’s confiscated umbrella. Her cheerful and exclamation-point-laden personality is a clever mask for her true identity as the legendary girl detective.

As her true self, Nancy is the architect of the entire March Hare Mystery. Unable to directly tell Rainy the truth about her parentage due to the rules governing fictional characters, she devises an elaborate mystery for Rainy to solve, knowing it is the only way for Rainy to achieve self-discovery. She is resourceful, intelligent, and deeply caring, driven by a long-held desire to connect with the sister she never got to know. Nancy’s role is metatextual; she is a character from one mystery series who creates a new mystery for the protagonist of another. This act makes her a key figure in revealing the novel’s central premise about Rainy’s own fictional nature.

X is the primary antagonist of the novel, a flat and static character who belongs to a group known as Burners. His central motivation is to destroy books that he deems “garbage” in order to preserve a canon of what he considers “true classics.” He is an elitist and a zealot, believing that by curating literature through destruction, he can create a more perfect world. His methods are destructive and direct; whereas Book Witches use umbrellas to delicately enter stories, X uses a lighter to burn holes in them, an act that illustrates his violent disregard for the integrity of narratives.

He and the Burners are physical and ideological foils to Rainy and the Book Witches, representing the real-world forces of censorship and destructive criticism. His actions directly embody the threat central to the theme of The Importance of Defending Stories, forcing the protagonists to actively protect narratives from those who would erase them.

Fanshawe is the leader of the Ink and Paper Coven and a minor antagonist for Rainy. She is a flat, static character defined by her rigid adherence to the Eight Black and Whites, the Coven’s code of conduct. Dr. Fanshawe represents the institutional authority and unbending binary thinking that Rainy frequently challenges. Fanshawe’s leadership style is stern and uncompromising, and she views Rainy’s emotional and rule-bending tendencies with constant disapproval. This disapproval is rooted in her fear that Rainy will follow her mother’s path and completely rebel against the coven. She creates an idealized portrait of Ellery as the perfect Book Witch to undermine Rainy. By constantly comparing Rainy to this idealized version of her mother, Fanshawe creates a significant source of internal and external conflict for the protagonist, forcing Rainy to fight for her own professional identity and methods.

Mrs. Turner is the March family’s housekeeper, a flat and static character who is a caregiver. Her personality is defined by her adherence to the traditions of a Victorian-era English domestic servant, providing order, tea, and doting care for Rainy, Pops, and Koshka. She is fiercely loyal and is a grounding, domestic presence within Pilcrow House. Her character carries a layer of thematic weight, as she is herself an escaped fictional character from the Sherlock Holmes stories who has become trapped in the real world and forgotten her origins. She is a living, breathing cautionary tale of what can happen when a character becomes disconnected from their narrative, her existence a constant, subtle reminder of the repercussions of breaking the rules.