John is a tall, handsome high school sophomore who copes with his stifling home life through drinking alcohol, smoking, and orchestrating elaborate practical jokes. He earns the nickname the Bathroom Bomber for setting off firecrackers at school, relying on his physical charm to evade punishment. Deep down, he harbors philosophical questions about his existence and deeply resents his father's attempts to force him into a traditional business career.

Lorraine is an introverted high school sophomore who moved to her current neighborhood two years prior. Fascinated by psychology, she frequently analyzes the behavior of those around her to understand their underlying anxieties. She suffers from low self-esteem fueled by her mother's constant verbal abuse, yet she displays a fiercely observant and highly empathetic nature when interacting with others.

Angelo Pignati is a retired electrician living in a rundown house on Staten Island. He maintains a quirky collection of ceramic pig figurines and delights in simple pleasures like telling corny jokes, performing memory tricks, and making daily visits to the zoo. Desperate for connection, he eagerly offers gifts and hospitality to John and Lorraine in exchange for their company.

Ms. Jensen is an overworked single mother who provides palliative care as a private in-home nurse. Harboring intense hatred toward men following her ex-husband's betrayal, she projects her anxiety onto Lorraine through strict rules and harsh criticism about her physical appearance. She struggles financially and occasionally steals small pantry items from her employers to make ends meet.

Norton is an aggressive teenager who socializes on the periphery of John's group. Having been mocked as a child for playing with dolls, he adopted a hyper-masculine, delinquent persona and frequently steals from local stores. He bears the hated nickname The Marshmallow Kid after getting caught shoplifting candy.

Mr. Conlan, whom John privately calls Bore, is a traditional man who works long days at the Coffee Exchange. He recovered from past alcohol abuse but remains emotionally distant from his youngest son. He expects John to abandon his acting dreams and follow a conventional corporate career path.

Mrs. Conlan, referred to as Old Lady by John, is a domestic housewife who focuses heavily on avoiding conflict and maintaining a quiet environment for her husband. She shows little active interest in John's emotional life and frequently compares him unfavorably to his older brother.

Kenneth is John's older brother who works successfully on Wall Street and is married. Though he does not actively appear in the daily events of the story, his obedient adherence to the American Dream sets an expectation in the household.

Dennis is a teenager who hangs out with John and Norton, frequently participating in their drinking and prank-calling sessions. He holds the current record for the telephone game by keeping an older woman on the line for over two hours.

Conchetta is the beloved wife of Angelo Pignati. Angelo keeps all her clothing, jewelry, and their shared collection of ceramic pigs perfectly preserved inside their Staten Island home.

Bobo is an aging baboon living at the local zoo. Mr. Pignati affectionately calls him his best friend, regularly feeding him peanuts and spending significant time at his cage.

Deanna is a student who works in the school's administrative office. Because she harbors a crush on John, she willingly hides his and Lorraine's absentee cards so they can skip classes undetected.

Miss Reillen is the school librarian who allows the teenagers to type their memorial project. John and Lorraine privately call her Cricket due to the distinctive sound her nylon stockings make when she walks.