Aven is a thirteen-year-old girl born without arms who relocates from Kansas to Arizona when her father accepts a job managing a rundown Western theme park called Stagecoach Pass. She performs daily tasks like eating, typing, and opening doors entirely with her feet. At her new middle school, she faces staring classmates and struggles to find a comfortable place to eat lunch in public. She copes with her social isolation by writing a blog and maintaining a sharp sense of humor about her physical differences.

Connor is a middle school student who has Tourette syndrome, which causes him to make involuntary vocal and motor tics. He lives in a small apartment with his mother and strictly avoids eating in public or visiting crowded places because strangers stare and mock him. He carries significant emotional weight, believing his medical condition caused his parents to fight and eventually divorce.

Zion is a shy, African American boy who isolates himself during the school day because he feels self-conscious about his weight. His parents are intense science fiction fans who named him and his brother after famous movie characters, a fact that mildly embarrasses him. He actively avoids the school cafeteria out of fear that other students will judge his eating habits.

Aven's adoptive father is a recently unemployed restaurant manager who moves his family across the country to take over daily operations at Stagecoach Pass. He shares his daughter's goofy sense of humor and bonded with her early in her childhood by teaching her to play soccer. He consistently requires Aven to attempt difficult physical tasks herself rather than relying on others for help.

Aven's adoptive mother works as the co-manager of Stagecoach Pass alongside her husband. She holds a degree in psychology and uses this background to help Aven transition to her new middle school. She actively encourages Aven to connect with other marginalized students and researches practical accommodations to make Aven's daily life easier.

Josephine is an eighty-year-old cook and waitress who has worked at Stagecoach Pass since the park opened decades ago. She observes Aven closely during her shifts, often giving the teenager unusual, knowing looks. She holds deep knowledge about the park's history and its mysteriously absent owner.

Henry is an elderly soda jerk at Stagecoach Pass who experiences dementia. He attempts unusual cleaning methods, like washing windows with whipped cream, but recalls events from the park's distant past with surprising clarity. He frequently makes confusing, cryptic remarks to Aven about tarantulas and rodeos.

Spaghetti is an elderly llama living at Stagecoach Pass. He has a large, visible tumor on his head that frightens park visitors away. Aven forms a special attachment to the animal because she understands the experience of being shunned for physical differences.

Connor's mother is an emergency room nurse who works demanding night shifts. Her exhausting schedule leaves her sleeping during the day and struggling to unpack the boxes in their new apartment. She desperately wants her son to have a normal social life but faces resistance from his deep-seated insecurities.

Zion's mother is an enthusiastic woman who embarrasses her son with her bubbly personality and unusual wardrobe choices. She loves science fiction media and wears a Wolverine t-shirt with a sparkly purple skirt when meeting his new friends.