TV-Series
Description
Hailing from Dokuro-sei (Planet Skull), Huesoduro (Kinkotsuman/Skullduggery) begins as an early antagonist before evolving into a recurring comedic foil. He frequently schemes alongside his accomplice Iwao, targeting the protagonists, especially through sabotage during major wrestling tournaments.

His personality blends self-proclaimed genius with deep-seated vengefulness toward the heroes, stemming from past defeats. This drives elaborate but inept plans, like using an invisibility gun during a strength contest or planting explosives on a lunar mission. These strategies consistently backfire, cementing his comic relief role. His relationship with Iwao involves comedic abuse, often physical.

A darker layer emerges from his strained relationship with his son, Bone Cold. Huesoduro's past abusive behavior—using Bone Cold as an outlet for frustration over losses—resulted in Bone Cold becoming an emotionally detached antagonist. Later reflections on this abuse prompt Huesoduro to reconsider his actions, fostering a slightly more empathetic demeanor.

Huesoduro demonstrates proficiency in inventing mechanical devices, such as the giant robot Ukon and brainwashing technology. He also possesses marksmanship skills, notably using a Chojin rifle during a critical match, an act that indirectly caused lasting injury. His skeletal design features a prominent "bone" (骨) kanji on his forehead, long white hair, black trousers, red accessories, and occasionally a transparent shirt revealing his structure.

His role shifts from primary antagonist to a peripheral figure who sometimes reluctantly supports the heroes. He appears among spectators during championship matches, even cheering for the protagonists despite their history. This culminates in his inclusion in the Justice Chojin cheering party, marking him as a reformed, though still mischievous, ally.

His arc spans multiple storylines: early kaiju extermination, the 20th Chojin Olympics, and the American Chojin Tag Tournament. During the latter, he creates the artificial Chojin "Black Shadow" as Iwao’s tag-team partner, only to suffer swift defeat. These experiences trace his journey from conquering villain to a figure whose failures and regrets foster incremental growth, particularly concerning his son and former enemies.