Sadayoshi Karimata stands as the primary antagonist, a feudal warlord who massacred the Ayuwatari clan to seize their advanced puppetry technology. Black hair, a mustache, and a ponytail mark his initial appearance, fitting his ruthless military bearing.

Driven by ambition to dominate the region, he ordered the extermination of the puppet-making family to obtain their creations, repurposing them as weapons. His forces killed Rangiku's father and siblings, though she escaped. His cruelty extended beyond this massacre; he sanctioned horrific experimentation where children were flayed alive to harvest their skin for puppet construction. This process grafted living flesh onto mechanical frames to enhance the puppets' combat capabilities. Rangiku herself bears a massive scar from her own father's forced skin removal under his influence.

As Rangiku pursued vengeance, Karimata remained active in his stronghold, deploying "deathless ninjas" and stolen puppets to maintain control. His tactics included psychological manipulation, leveraging the tragic origins of the puppets to demoralize opponents. During the final confrontation, he personally confronted Rangiku and her ally Yasaburo Manajiri, confident in his stolen puppet's superiority. He explicitly stated Rangiku could only control one puppet at a time, attempting to exploit this perceived limitation. However, she countered with an illusion-assisted strategy, making him believe she deployed multiple puppets. This misdirection allowed her to disguise herself as one puppet while he attacked a decoy, creating the opening needed for his defeat.

His demise occurred during this battle, overcome by Rangiku's tactics. His legacy is defined by tyranny, the perversion of puppetry for warfare, and the irreversible trauma inflicted through his atrocities.