Imotaro Gorira, nicknamed Goriraimo ("Gorilla-Imo"), reigns as the primary school bully and persistent rival to the protagonist. Introduced as a hot-tempered antagonist, he clashes physically and verbally with peers, fixating on the protagonist due to a romantic rivalry over a female classmate. His towering physique and aggressive posturing cement his dominance within school hierarchies.

Though initially one-dimensional, his arc reveals gradual complexity. While retaining a fiercely competitive streak, he shifts from outright hostility to joining collaborative pranks and humorous schemes with former adversaries, hinting at grudging camaraderie. His family’s fish shop weaves into his identity, with later narratives showing him inheriting the business as an adult.

Beneath his abrasive exterior lies an unexpected softness: a deep affection for cats, a vulnerability that contrasts his rough persona. His dynamic with Mogura—a mole-themed sidekick whose tunneling skills complement Goriraimo’s brute strength—underscores their contrasting yet symbiotic partnership.

Expanded media briefly explores his adulthood, depicting him managing the fish shop while maintaining ties to former classmates. This progression from foe to occasional ally highlights themes of growth and reconciliation, though his core identity—marked by physicality, rivalry, and loyalty to his roots—persists unaltered across all storylines.