Bobby's younger sister, a mathematical prodigy whose struggles with schizophrenia and untimely death impact her brother deeply. Her complex mindset and hallucinations are central to her character's narrative arc.

A hallucination experienced by Alicia, he manifests as an antagonistic and clever presence. His interactions with Alicia provide insight into her internal conflicts and perceptions.

A friend of Bobby's who is intellectual, cynical, and serves as a confidant. He frequently discusses themes of grief and regret and provides significant insight into Bobby's psychological state.

A close friend of Bobby's and a transgender woman who recounts her challenging life experiences. Her views on life and God align closely with those of Bobby's grandmother, Granellen.

Bobby's coworker and a Vietnam War veteran, who is ultimately killed during a salvage dive. His common-sense outlook on life contrasts with Bobby's intellectualism, and he acknowledges Bobby's struggles with the past.

Bobby's and Alicia's maternal grandmother, who provides care and comfort to Bobby. Her lifestyle is rooted in simplicity and acceptance, offering a different perspective on life's challenges.

A private investigator who assists Bobby after he encounters trouble with federal agents. Formerly a fortune teller, Kline offers practical, straightforward advice to Bobby on how to navigate his predicament.