Cassie is a 32-year-old artist living in Chicago who struggles to find consistent, well-paying work in her field. She works part-time at the public library's children's department and picks up shifts at a hipster coffee shop called Gossamer's. Her art involves scavenging for discarded materials and trash, which she turns into contemporary sculptures. Fiercely independent, she refuses financial handouts and opts to rent a suspiciously cheap room in Lincoln Park to solve her housing crisis.

Frederick is a vampire over 200 years old who recently awoke from a century-long coma. Originally from an 18th-century English village, he dresses in three-piece suits, uses formal language, and adheres to antiquated social rules. He places an ad for a human roommate hoping they will help him adapt to 21st-century Chicago. He survives by drinking stolen supplies from blood banks rather than hunting humans.

Edwina is Frederick's mother, a traditional vampire who still feeds directly on humans. She dresses in dark, Victorian-style clothing with intense makeup. She holds strict, old-fashioned views on vampire society and actively pressures her son to fulfill an arranged marriage agreement.

Sam is a lawyer and Cassie's oldest friend. He lives in a small lakefront condo in Chicago with his husband, Scott. Financially stable and protective, he frequently offers to loan Cassie money or accommodate her living situation, though he respects her need to solve her own problems.

Reginald is a 35-year-old-appearing vampire and Frederick's longtime companion. He possesses a chaotic, fun-loving personality that contrasts with Frederick's stiff formality. He is the one who accidentally poisoned Frederick with a botched spell, putting him to sleep for a century, but he also protected him during that time.

Scott is Sam's husband, living with him in a small Chicago condo. He supports Cassie's artistic ambitions and points her toward local competitions to help advance her career.

Esmeralda is a wealthy vampire belonging to the prominent Jameson family. She is the intended bride in an arranged marriage with Frederick. She maintains an active social media presence, documenting her international travels and glamorous lifestyle.

Amelia is Sam's sister. Cassie avoids moving in with her because she feels Amelia judges her life choices. She later attends a party at Sam's condo, where she bonds with Frederick.

David is the head of a local modern art competition. He makes the final decisions regarding which artists receive funding and gallery space, directly impacting Cassie's career trajectory.

Marcie is Cassie's boss at the Chicago public library. She oversees the children's department and manages the various community events Cassie helps facilitate.

Nanmo is Edwina Fitzwilliam's assistant. He handles her administrative tasks and electronic correspondence, managing her affairs when she cannot.