Romiette is a sixteen-year-old African American junior at Thomas Jefferson High School in Cincinnati. She works part-time at her mother's boutique and maintains strong academic records. Having never learned to swim, she suffers from a recurring nightmare where she is trapped underwater and unable to breathe. Her straightforward high school routine changes when she meets a transfer student online under the screen name 'afroqueen' and agrees to meet him in the cafeteria.

Julio is a sixteen-year-old Mexican American student who recently relocated from coastal Texas to Cincinnati. His parents moved the family to escape the gang violence that plagued his previous school, a decision Julio actively resents. He misses the warm weather, his grandfather's ranch, and his golden retriever. Going by the screen name 'spanishlover' online, he connects with a local girl before realizing they attend the same high school.

Destiny is Romiette's enthusiastic best friend. She approaches life with a strong belief in astrology, cosmic alignment, and fate. She purchases a 'Scientific Soul Mate System' kit to help uncover her predetermined romantic partner before the school prom. She provides loyal support to Romiette, even when she worries that fire and water astrological signs might not mix.

Ben is a white student at Thomas Jefferson High School who embraces his status as a social outcast. He routinely dyes his hair bright colors, like green or orange, and ignores the established social hierarchy of the school. He actively chooses to extend grace to Julio after a physical altercation in the hallway, covering for the new student and initiating a fast friendship.

Luis is Julio's father. He moves his family from Corpus Christi to Cincinnati in hopes of providing a safer environment for his son. He carries deep psychological scars from his teenage years, when a local gang killed his first girlfriend. This past tragedy causes him to view his son's new relationship with intense suspicion and fear.

Julio's mother acts as a calming presence in the Montague household. Unlike her husband, she takes a more relaxed and understanding approach to Julio's adolescent experiences. She recognizes the positive effect Romiette has on Julio and actively advises him to relax and trust his feelings.

Cornell is Romiette's father and a prominent evening news anchor in Cincinnati. He takes pride in his career and relies on his professional success to provide a stable, comfortable life for his family. He believes the Cincinnati school system is relatively safe compared to larger cities, initially dismissing the possibility of organized gang activity in his daughter's school.

Romiette's mother is an entrepreneur who owns and operates a high-end fashion boutique specializing in African artifacts. She provides a warm, culturally rich home environment for her daughter. She greets Julio enthusiastically when he visits their home to pick out a golden retriever puppy, modeling an open-minded approach to parenting.

Malaka is a former childhood friend of Romiette. After her parents went through a divorce, she changed her social circles and began associating with the Devildogs, a local gang that wears purple hoodies. She visits the boutique to deliver a direct threat to Romiette regarding her new relationship.

Nannette is an incompetent and sensationalist local news anchor. She prefers reporting on lighthearted, superficial news stories, such as a farmer finding a two-headed frog, over serious investigative journalism. Her careless approach to journalism and tendency toward reckless speculation frequently annoy her colleagues.

Diego is Julio's best friend from Corpus Christi, Texas. The two boys previously bonded over their shared refusal to participate in the gang culture that dominated their Texas high school. He stays in contact with Julio via phone calls, offering advice from afar.

Angelina was Luis Montague's teenage girlfriend in Corpus Christi. She lost her life when a carload of gang members chased her and Luis across an open field, an event that permanently altered Luis's perspective on safety and race.