The character "Puchi" is the protagonist named Banner in the original Japanese version and Puschel in German adaptations, specifically identified as Puchi in the third Portuguese dub.

Orphaned as an infant after his nest's destruction, Puchi was adopted and raised by a farm cat who treated him as her own. This feline upbringing fostered exceptional bravery and combativeness uncommon in squirrels. The cat placed a bell around his neck, which became a permanent fixture. A barn fire forced him apart from his adoptive mother, driving him into the forest.

Initially struggling to reconcile his cat-raised instincts with his squirrel nature, Puchi gradually adapted to wild squirrel society. His unique background allowed him to confront predators directly, often using strategy to protect others. He forged strong bonds, including a close friendship with a younger squirrel, Clay, whom he rescued from a fox, and a romantic relationship with Sue, a female squirrel who aided his integration. Their courtship faced rivalry from another squirrel, Akācho, who employed underhanded tactics like tricking Puchi into consuming hallucinogenic mushrooms.

Puchi endured substantial losses, witnessing his mentor, Uncle Owl, sacrifice himself by intercepting a bullet meant for him. His journey included hardships like false theft accusations, the need to relocate his community due to logging, and a perilous migration to a new forest. Throughout, he persisted in altruism, even helping former tormentors. The series culminated in his reunion with the adoptive mother cat, marriage to Sue, and the birth of their offspring, marking resolution to his arduous adaptation and survival struggles.