Jackson is a logical, observant boy who has just completed the fourth grade and aspires to be an animal scientist. He strongly prefers concrete facts over fiction, actively disliking stories because he equates them with lies. As his family experiences severe financial instability, Jackson internalizes his stress and attempts to shoulder adult burdens. He resists acknowledging his own need for comfort when his childhood imaginary friend suddenly reappears.

Crenshaw is a human-sized tuxedo cat who enjoys skateboarding, doing cartwheels, and taking bubble baths. He acts as Jackson's imaginary friend, originally appearing when Jackson's family first experienced homelessness years prior. He returns to Jackson's life just as familiar signs of poverty begin to surface again, sharing his creator's fondness for purple jelly beans and honesty.

Tom is Jackson and Robin's father. Formerly employed in construction, he had to quit building houses after receiving a multiple sclerosis diagnosis, and his subsequent handyman business suffers due to his physical limitations. He experiences intense shame regarding his inability to provide for his family and resists seeking help from social services. He often uses forced optimism and humor to deflect serious conversations about money.

Sara is Jackson and Robin's mother, a former middle school music teacher who lost her position due to budget cuts. She works multiple part-time jobs, including shifts as a waitress and at a pharmacy, to keep the family afloat. While she tries to maintain a cheerful demeanor for her children, she is more practical than her husband and actively pushes him to accept government assistance.

Marisol is Jackson's best friend and business partner in their neighborhood dog-walking service. She lives in the Swanlake Village apartment complex and spends much of her time with a caregiver while her parents travel for work. While she shares Jackson's scientific curiosity and dreams of becoming a paleontologist, she also fully embraces imagination and the unknown.

Robin is Jackson's five-year-old sister. She carries a stuffed armadillo named Spot and frequently requests readings from her favorite book, *The House on East 88th Street*. She clearly remembers the family's previous stint living in their minivan and expresses deep anxiety about the prospect of losing their home again.

Aretha is the family's large, affectionate dog. She occasionally behaves strangely around Crenshaw, sniffing him, playing tug-of-war, or running away in fright. Her reactions cause Jackson to question whether his imaginary friend might actually have a physical presence, or if the dog is simply reacting to Jackson's own stressed body language.

Ms. Malone is Jackson's fourth-grade teacher. She teaches her students about the altruistic behavior of vampire bats, an animal fact that heavily influences Jackson's perspective on human nature, fairness, and community support.

Paula is a caretaker who watches over Marisol while Marisol's parents—a pilot and a salesman—are traveling for work.

Whoops is Marisol's former imaginary friend. Characterized as a naughty girl, she served as a convenient scapegoat for Marisol's misbehavior when Marisol was younger.

Finian is an imaginary friend who plays the guitar. Crenshaw uses Finian's existence to prove to Jackson that adults also rely on imaginary companions for comfort during difficult times.

Kylie is Robin's friend. She hosts a birthday party where Robin obtains a handful of purple jelly beans, which Robin later hides in a baseball cap to convince Jackson that magic is real.