Shinnosuke Nohara is a five-year-old Japanese boy living in Kasukabe, Saitama Prefecture, with his father Hiroshi, mother Misae, younger sister Himawari, and the family dog Shiro.

Energetic and mischievous, Shinnosuke often performs socially inappropriate antics like his signature "hip-shaking dance" in public or making bluntly embarrassing observations about adults. He speaks with a distinctive, rough, and informal style, using the self-referential "Ora" and addressing his parents as "Hiroshi" and "Misae" rather than traditional honorifics.

Though typically self-centered, prioritizing snacks, television, and play over responsibilities, Shinnosuke occasionally reveals surprising emotional insight. He shares an unconventional but strong bond with his family—teasing his sister and annoying his parents, yet showing genuine protectiveness in difficult moments. He forges loyal friendships with peers Kazama, Nene, Masao, and Bo, navigating Futaba Kindergarten dynamics with his unique perspective.

His vivid imagination fuels elaborate fantasies, often starring his superhero alter-ego "Action Kamen". He thrives on outdoor play, action-hero shows, and snacks like "Chocobi" chocolate. Fearless around authority figures and new situations, his high energy leads him into both trouble and unexpected adventures.

In "Eiga Crayon Shin-chan: Ora no Hikkoshi Monogatari ~Saboten Daishūgeki", Shinnosuke's family relocates to Mexico City for Hiroshi's job. Facing culture shock, language barriers, and separation from friends, he struggles to adapt to a new kindergarten. There, he befriends a local girl, Avi, and becomes entangled in an adventure involving a legendary giant cactus monster. Confronting homesickness and unfamiliarity, Shinnosuke matures slightly—embracing his new environment while protecting his friend and community, showcasing resilience alongside his trademark boldness.