Tyler is a seventeen-year-old high school senior undergoing a major physical and social transformation. Sentenced to probation and community service after vandalizing school property with spray paint, his summer of manual yard work has added significant muscle to his previously slight frame. He deals with severe insecurity and a difficult home life, often relying on dark thoughts about death as a coping mechanism for his anger.

Bill is Tyler's father, a heavily stressed executive employed by Brice Milbury. He suffers from high blood pressure and isolates himself in his basement retreat, listening to opera to avoid dealing with his family. His approach to parenting oscillates between completely dismissing Tyler and engaging in explosive, angry outbursts regarding his son's grades and future.

Hannah is Tyler's younger sister, an incoming freshman at George Washington High who eagerly anticipates the social complexities of her new school. She is assertive, sports a hidden belly button ring, and joins the field hockey team to establish her status. She is keenly aware of how appearance and associations affect social standing.

Linda is Tyler's mother, a pet photographer and cake baker who self-medicates with alcohol to manage her stressful household. She frequently attempts to act as a buffer between her husband and her children, defending Bill's behavior to Tyler while privately retreating from conflict.

Bethany is one of the most popular girls at Tyler's high school, as well as the daughter of his father's boss. She begins to notice Tyler after his physical transformation and summer of infamy. She enjoys his attention but operates comfortably within the upper echelons of the school's social hierarchy, making her interactions with him unpredictable.

Chip is Bethany's twin brother and a prominent figure in the school's popular crowd. He is an aggressive athlete who frequently targets weaker students. He resents Tyler's sudden physical growth and goes out of his way to intimidate him, acting highly protective of his sister and his own social standing.

Calvin, known to everyone as Yoda, is Tyler's best friend and summer coworker. Unlike Tyler, Yoda has not undergone a physical transformation and remains a frequent target for bullies like the junior varsity football players. He is generally optimistic, emotionally articulate, and steadfastly loyal.

Principal Hughes is the lead administrator of the high school who keeps a close eye on Tyler due to his prior vandalism conviction. He attempts to maintain order and enforce the dress code, balancing basic fairness with the strict oversight required to manage daily school conflicts.

Joe is a member of the high school's maintenance staff who supervises Tyler during his summer community service on the building's roof. He serves as a quiet, positive adult figure, offering brief but meaningful encouragement when Tyler feels isolated.

Mr. Salvatore is Tyler's demanding AP English teacher who initially fails Tyler on a bluffed paper about John Milton. He later proves to be surprisingly empathetic, offering one-on-one tutoring and moral support when Tyler faces intense isolation from his peers.

Mr. Benson is Tyler's assigned probation officer following his vandalism charge. He tracks Tyler's progress, reminding him to stay out of trouble while providing generally fair assessments of his behavior.

Brice and Dolores are Bethany and Chip's wealthy parents. Brice owns the company where Tyler's father works and operates under the stress of a federal investigation. They represent the upper crust of the local community, openly admiring Tyler's new physique while expecting absolute perfection from their own children.

Acting as a collective force within George Washington High, the student body constantly generates and spreads rumors. They react heavily to Tyler's physical changes and play a critical role in socially isolating him when controversial photos begin circulating online.

Parker is a junior varsity football player and one of Chip Milbury's friends. He actively participates in locker room bullying and frequently interacts with the popular girls, using his athletic status to avoid consequences.

Officer Adams is a local police officer tasked with investigating an incident involving the distribution of explicit photos. He employs leading questions and intimidation tactics to pressure suspects during home interrogations.

Mr. Pirelli is Tyler's boss at the summer yard care company. He assigns strenuous manual labor tasks and offers practical, tough-love advice about building calluses and handling physical pain.