Hachirō Kariage, father of Evilus Kariage and son-in-law of Maneko Kariage, occupies a marginalized position as an unwelcome adopted member of the Kariage family. He endures constant belittlement and disrespect from Maneko and others, maintaining a quiet, submissive demeanor to avoid conflict, often overlooked or dismissed in daily life.

His background as a former flyweight world boxing champion surfaces dramatically within a boxing ring. Entering the ring triggers a profound transformation, shifting him from passivity into the strongest boxer, surpassing even Starzan S in combat prowess. His physicality, expression, and voice become markedly serious and focused during these episodes, starkly contrasting his domestic persona.

A recurring aspiration involves his desire for the restoration of male authority, which he associates with the legendary utopia Paratopia. This reflects his underlying dissatisfaction with his diminished family role and hope for a societal shift validating his identity. Despite pervasive disrespect, moments of genuine care and affection toward his family, particularly his wife Liz Kariage, indicate authentic feelings persist beneath his strained circumstances.