Ethan is a sixteen-year-old high school student who longs to escape the close-minded Southern town of Gatlin. He grieves the recent loss of his mother and deals with a distant father who isolates himself in his study. Unlike his peers, Ethan possesses an open mind and a strong sense of empathy. He feels an immediate, unexplainable draw to the new girl at school.

Lena is a fifteen-year-old Caster who possesses the ability to manipulate natural elements. She lives with her reclusive uncle at Ravenwood Manor and faces constant harassment from her mortal classmates. Lena experiences intense anxiety about her upcoming sixteenth birthday, a day when she will be Claimed for either Light or Dark magic without any personal choice.

Macon is Lena's uncle and the most infamous recluse in Gatlin. He lives in the crumbling Ravenwood Manor and never leaves the property during the day, making him the subject of local ghost stories and gossip. He acts as Lena's guardian, dedicating his vast resources to protecting her from the dark forces of their world.

Amma is the Wate family's housekeeper and Ethan's primary caregiver following his mother's death. She possesses deep ties to the supernatural through her African heritage and practices voodoo to protect the Wate household. She communicates with her ancestors, known as The Greats, and monitors the supernatural activity surrounding Ravenwood Manor.

Sarafine is the Darkest Caster alive and Lena's mother. Initially believed to be dead, she operates from the shadows to influence Lena's impending Claiming. She represents the terrifying possibility of what Lena could become if claimed for the Dark.

Link is Ethan's loyal and easygoing best friend. He provides comic relief and unwavering support for Ethan, even when Ethan's choices make him unpopular at school. Link plays in a band and maintains a casual attitude toward the rigid social hierarchy of Gatlin High School.

Mrs. Lincoln is Link's mother and the rigid leader of the Daughters of the American Revolution (DAR) in Gatlin. She acts as the town's primary moral enforcer and gossipmonger. She organizes a crusade to expel Lena from school, using biased language and Southern prejudices to rally the town against anyone different.

Ridley is Lena's cousin and former best friend who was claimed for the Dark on her sixteenth birthday. As a Siren, she possesses the power of persuasion, easily manipulating mortals to do her bidding. She returns to Gatlin to stir up trouble and taunt Lena about her approaching birthday.

Aunt Del is a member of the Duchannes family and mother to Ridley, Larkin, Reece, and Ryan. She possesses the ability to pass through time and attempts to maintain peace within the fractured, supernaturally divided family.

Larkin is Lena's cousin and an Illusionist. He participates in the family's magical traditions and frequently helps Lena bypass the strict rules of Ravenwood Manor.

Reece is one of Lena's cousins and a member of the magical Duchannes family. She participates in family events and assists Lena when exploring the history of their Caster ancestors.

Ryan is the youngest of Lena's cousins. Her magical abilities are still developing, but she occasionally demonstrates a talent for healing. The family carefully shields her from the darker aspects of their world.

Ethan's father is a grieving widower who spends his days locked in his study, supposedly writing a book. His deep depression leaves him detached from Ethan's daily life, forcing his son to rely on Amma for parenting and emotional support.

Marian is the town librarian and the former best friend of Ethan's late mother. Secretly, she serves as a Keeper—a mortal entrusted with recording the history of Casters. She provides Ethan and Lena with crucial historical context regarding the Duchannes family curse.

Genevieve is Lena's Civil War-era ancestor. A powerful Caster, she fell in love with a mortal soldier and made a desperate magical bargain to save his life. Her actions initiated the curse that dictates the fate of every Duchannes descendant.

Ethan Carter Wate is Ethan's historical ancestor from the Civil War era. He deserted the Confederate Army due to his moral objections and deeply loved Genevieve Duchannes, setting off a chain of tragic, magical events.

Ivy is Genevieve's cook during the Civil War era and an ancestor of Amma Treadeau. She possesses spiritual abilities connected to the Otherworld and warns Genevieve about the dangerous consequences of using dark magic.

Emily is a popular cheerleader at Gatlin High School. She aggressively bullies Lena, organizing cruel pranks and taunting her about living in the Ravenwood Manor.

Savannah is one of the most popular girls at Gatlin High School. She participates in the systemic bullying of Lena and helps enforce the town's rigid, prejudiced social norms.

Boo Radley is Macon Ravenwood's Caster dog. He freely roams the town of Gatlin at night, serving as Macon's eyes and ears to gather secrets about the townspeople.

Mr. Lee is a history teacher at Gatlin High School. He embodies the town's revisionist, prejudiced view of the past, famously giving Ethan a poor grade for referring to the Civil War as the "War of Southern Aggression."

Hunting is Macon's brother. He aligns himself with the darker forces in the Caster world and shares a tense, combative history with Macon.

The Sisters are Ethan's elderly great-aunts. They serve as the town's unofficial historians and possess deep knowledge about the lineage and secrets of Gatlin's oldest families.

Lena's grandmother is the matriarch of the Duchannes family. She possesses powerful magical abilities that allow her to transfer energy between family members during times of crisis.