Gashim is a kindhearted, elderly makemono, a demon-beast race forged in the apocalyptic wake of the Overfiend's rise. Initially imprisoned under the mutant warlord Caesar, who enslaved this new race, Gashim gained freedom during the beasts' bloody coup against Caesar's regime. Following his release, he joined the surviving makemono, aligning with Buju, Himi, Amano Jyaku, and others on their perilous journey toward Osaka. Their goal was to confront the Chōjin residing within Osaka Castle, the epicenter of the cosmic conflict. Within this group, Gashim's demeanor contrasts with more aggressive members like Buju, embodying a gentler resilience amidst their harsh, ruined world. His role is consistently supportive within the ensemble, contributing to their collective survival struggle and overarching mission.