Macy is a 22-year-old college graduate living in a tiny converted-motel apartment in Salem, Oregon. Burdened by heavy debt and facing eviction, she is financially desperate and accepts a highly suspicious caretaking job out of pure necessity. She struggles with deep depression and the unresolved sorrow of losing her father three years earlier. Though fiercely protective of her younger sister, her emotional detachment and reliance on strict coping mechanisms leave her vulnerable to the psychological toll of her new role.

The Visitor is a malevolent, shapeshifting supernatural entity confined to the Carnswel property. It operates as a parasitic force, deriving power from the psychological vulnerabilities and unhealed wounds of the property's caretakers. Capable of assuming the exact physical forms of deceased or beloved individuals, it weaponizes intimate memories and insecurities to cause pain. Its defining physical characteristic across all its human manifestations is a pair of pale, unnatural blue eyes.

David is Grace's late husband and the original caretaker of the Brooksview Heights property. Driven by profound grief over the death of his son, he established a strict set of arbitrary rules called the "Rites" to contain the malevolent entity on his land. He leaves behind a degraded VHS tape and sealed contingency envelopes to instruct his successor on how to survive. His meticulous routines act as a psychological fortress against his own trauma.

Jemma is Macy's 17-year-old sister who lives with her in a dilapidated Salem apartment. Grounded, pragmatic, and highly cynical, she consistently serves as the narrative's voice of reason, instantly recognizing the danger of the Craigslist job. She relies on Macy for financial support, including her asthma medication, but loudly protests her sister's willingness to accept dangerous work. She exhibits a rebellious streak through occasional shoplifting, which she justifies as balancing corporate scales.

Grace is the wealthy widow of David Carnswel who hires Macy under vague and deceptive pretenses. She portrays herself as a down-to-earth woman but actively dismisses her late husband's routines as superstitious nonsense brought on by dementia. Despite her stated skepticism, she is willing to pay an exorbitant sum of money to ensure David's final wishes are honored while she conveniently leaves for Florida. Her ambiguity leaves others questioning how much she truly knows about the property.

Lucy is a melancholic hiker and the former house cleaner for the Carnswel estate. She frequently visits the local cliffs to prevent people from jumping, carrying a heavy emotional burden from her past. Friendly but prone to oversharing, she warns Macy about her previous employment, explaining she was fired for sleeping through David's required lighting routines. She becomes a tragic figure entangled in the property's supernatural orbit.

Caleb is David Carnswel's deceased son, whose tragic death long precedes the events of the novel. His passing acts as the foundational trauma that anchors David to the Brooksview Heights property and the strict observance of the Rites. The supernatural entity occupying the land uses Caleb's exact appearance and memories to inflict maximum psychological damage on his grieving father.

Greg is the insurance broker handling the policy of Macy's late father. He delivers a significant blow to Macy's financial stability when he informs her that the insurance company is moving to deny the life-insurance payout. He shares previously unknown details about her father's past, complicating her understanding of her family history.

Brienna, also known as "Zee," is Lucy's deceased childhood best friend. She possessed a beautiful singing voice, and her loss is a source of profound, unresolved sorrow for Lucy. Her memory becomes a focal point of vulnerability when supernatural forces begin manipulating those near the Carnswel property.

Avery Beckett is a former classmate of Macy's who broke her heart after a brief four-month relationship. Avery's departure reinforced Macy's defensive habit of ending relationships prematurely to avoid being hurt, shaping her emotionally detached approach to the world.