Hulda is a 34-year-old investigator for the Boston Institute for the Keeping of Enchanted Rooms (BIKER). She possesses a 12% magical talent for augury, allowing her to catch brief glimpses of future events. Following past romantic rejections, she maintains a scrupulously modest, schoolmarmish appearance and dedicates herself entirely to her profession. She approaches unruly magical properties with firm practicality, utilizing tools like her crowbar, protective wards, and communion stones to establish order.

Merritt is a 31-year-old former journalist and current novelist who unexpectedly inherits the remote Whimbrel House on Blaugdone Island. Disowned by his father thirteen years ago, he lives a mostly solitary life. He possesses a gentle nature and a quiet desire for connection but remains emotionally guarded due to the sudden disappearance of his former fiancée.

Silas is a powerful English wizard and necromancer who vows never to let anyone hold authority over him following a traumatic youth. He discovers a grim ability to steal magic from other people and enchanted houses, binding their power to himself by shrinking his victims into withered dolls. He operates with intense self-interest and seeks vengeance against the woman who reported his activities to the King's League of Magicians.

Myra is an attractive, divorced woman in her late forties who serves as the head of the Boston Institute for the Keeping of Enchanted Rooms (BIKER). She is highly ambitious and intensely focused on keeping her institution viable in an era when enchanted homes are vanishing. She values her employees' safety but often prioritizes the survival of BIKER.

Owein is the spirit of a twelve-year-old boy who died over a century ago and now inhabits Whimbrel House. Separated from his family in death, his loneliness manifests as mischievous and sometimes dangerous tantrums directed at the home's occupants. He communicates his moods by physically altering the architecture, from melting furniture to tilting floors.

Beth is a capable young maid hired to help maintain order at Whimbrel House. She possesses a magical talent for psychometry, giving her intuitive feelings about objects and letters. Her experience working in enchanted homes makes her entirely unbothered by the supernatural quirks of her new workplace.

Baptiste is a French chef who is down on his luck until Merritt impulsively hires him off the street. He quickly adapts to the bizarre environment of Whimbrel House, focusing on his culinary duties rather than the magical occurrences around him.

Fletcher is Merritt's closest and most reliable friend. He provided Merritt with a place to live after his family disowned him and continues to offer practical help and advice. He is observant regarding Merritt's social and romantic life.

Ebba is a flutist and Merritt's former fiancée from his teenage years. Her sudden disappearance thirteen years ago—after claiming to be pregnant—resulted in Merritt being disowned by his family and left him with lingering emotional scars.

Lord Hogwood is Silas's magically gifted father who was dismissed from the King's League of Magicians. He takes out his professional anger and resentment on his son, utilizing his magical abilities to physically abuse him.

Christian is Silas's magically gifted younger brother. He possesses kinetic powers and grows increasingly suspicious of Silas's secretive actions and the sudden disappearance of their mother.

Mr. Clarke is an employee of the Genealogical Society for the Advancement of Magic. He views the preservation of magical bloodlines as a societal imperative and actively tries to recruit magically gifted individuals into arranged marriages.