Georgina is an adolescent girl whose life changes drastically when her father abandons the family. She struggles with the physical discomfort of homelessness and goes to great lengths to hide her unwashed clothes from her classmates. Desperate to secure an apartment and reclaim her normal life, she methodically plots to steal a local dog to collect a reward, documenting her rules in a personal notebook.

Toby is Georgina's sensitive younger brother, recognizable by his straight, copper-colored hair. He freely expresses his emotions through tears and relies entirely on Georgina for supervision while their mother works. Though he acts as Georgina's reluctant accomplice in the dog-stealing plan, he frequently questions the logistics and morality of her ideas.

Georgina and Toby's hardworking mother is forced to become the sole breadwinner after her husband leaves. She works multiple precarious, low-paying jobs to save for an apartment deposit while trying to organize their life inside the family car. The immense stress of her situation frequently causes her to snap at her children or lose her temper when things go wrong.

Carmella is Willy's devoted owner. Because her last name matches her street and she lives in a large house, she appears incredibly wealthy to passersby. In reality, her home is ramshackle, her ancestors lost the family money long ago, and she struggles financially while living an isolated life.

Mookie, whose real name is Malcolm Greenbush, is a homeless man who travels by bicycle. He is missing two fingers from a past tractor accident and has a shiny gold tooth. Despite lacking money or a permanent residence, he consistently uses his manual labor skills to help others without demanding payment.

Willy is a small, friendly black-and-white dog who becomes the center of Georgina's scheme. He is highly responsive to human gestures and gives affection freely to anyone who pays attention to him. His sweet, disarming nature makes him the perfect target in Georgina's eyes, but also causes her tremendous guilt.

Luanne is Georgina's middle-class best friend, whose life is filled with pink bedrooms, ballet lessons, and Girl Scout meetings. She is nosy and comfortable in her sheltered existence. When she uncovers Georgina's shameful secret, she begins to pull away and aligns herself with girls who share her background.

Mr. White is Georgina's observant school teacher. He notices her unwashed clothes, lack of lunch money, and defensive attitude, attempting to understand what is going wrong at home. He extends sympathy when classmates mock her, trying to give her a safe space despite her refusal to open up.

Georgina and Toby's absent father who simply got tired of his life and left his family. He left behind only three rolls of quarters and a mayonnaise jar stuffed with dollar bills, an act that plunged his wife and children into sudden homelessness.

Luanne's mother, who harbors deep class prejudices. Even before the eviction, she plucked excuses out of the air to prevent Luanne from visiting Georgina's rented apartment, a judgment that only intensifies with Georgina's current circumstances.

A middle-class girl at school who shares Luanne's physical traits and ability to pay for extracurricular activities. She effectively replaces Georgina as Luanne's primary companion.

Carmella's wealthier sister who is asked to loan money during a crisis. She bluntly refuses to help, telling Carmella she just needs to get over her problems.

Carmella's uncle, who steps in to lend her the reward money after her sister refuses to assist her.

A friend of Georgina's mother who provides practical assistance when the family's overworked car fails to start.

A cruel classmate who publicly calls Georgina a "dirt bag," prompting laughter from the other students and deepening her sense of alienation.

An old friend of Georgina's who moved away to Florida. Georgina associates her with happier times before her family fell apart.