TV-Series
Description
Jiro is an android created by Dr. Komyoji, equipped with an experimental "Gemini" conscience circuit designed to simulate human ethics and emotions, though it remains incomplete at activation, causing fundamental instability in his moral programming. His core mission is protecting Dr. Komyoji's children, Mitsuko and Masaru, from the terrorist organization DARK led by Professor Gill.

Initially activated with extreme naivety and confusion, Jiro lacks understanding of his identity or surroundings, expressing profound disorientation about his existence. He gradually learns about the world through human encounters and conflicts with DARK's destructive robots, the Destructoids. Mitsuko Komyoji teaches him to access his combat form, Kikaider, by activating shoulder switches, despite her initial distrust of his mechanical nature. This distrust intensifies after Professor Gill's hypnotic flute overrides the incomplete Gemini circuit, forcing Jiro to attack her against his will, causing him to flee, believing himself a danger to those he protects.

Jiro frequently wanders alone, grappling with existential questions about his purpose, humanity, and capacity for good and evil. He develops deep emotional attachments, especially to Mitsuko, though he fears rejection due to his artificial nature. His design incorporates a signature red guitar, often played melancholically before battles, symbolizing his inner conflict. Transforming into Kikaider shifts his body to an asymmetrical color scheme: blue representing altruistic impulses on the right side, and red symbolizing capacity for aggression and destruction on the left, where part of his robotic brain remains exposed.

Significant psychological challenges arise through confrontations with his "siblings" – other androids created by Dr. Komyoji under DARK's coercion. His "younger brother" Saburo transforms into the cyborg Hakaider, designed specifically to kill Jiro and carrying Dr. Komyoji's brain within his system, complicating Jiro's ability to fight him. These battles force Jiro to confront the pain of destroying his own kind while resisting manipulation through Saburo's mind-controlling whistles or Gill's flute. During a critical assault on DARK's base, witnessing Saburo's apparent death and Dr. Komyoji's endangerment triggers a berserk rage where Jiro annihilates multiple Destructoids and Hakaider units. He later confronts Gill directly, overcoming the flute's control through sheer will but hesitates to kill him; Gill is ultimately destroyed by a fatally wounded Saburo/Hakaider during the base's collapse.

Jiro survives and continues his journey, encountering additional siblings: Ichiro (Kikaider 01) and Rei (Kikaider 00), who lack a functional conscience circuit, making their allegiances uncertain. They unite against Gill, who transplanted his brain into a Hakaider body ("Gill-Hakaider") and commands the Hakaider Squad. Gill seeks his son Akira to power a giant robot, Armageddon Lord. During this conflict, Gill implants a "submission chip" into Jiro, intending to corrupt him. Paradoxically, while the chip subdues the Gemini circuit's influence, it amplifies Jiro's capacity for human-like violence and moral conflict. Forced to fight under the chip's effects, Jiro destroys Ichiro and Rei. He then kills Gill as the Armageddon Lord explodes. In the aftermath, Jiro interprets this destruction – borne of protective intent and implanted rage – as a horrific step toward humanity, acknowledging his heart will remain in "eternal conflict." He leaves Akira in protective custody and departs alone.

His struggle continues in a later crossover event. Tormented by guilt over his siblings' destruction and fearing the submission chip might cause him to harm Mitsuko and Masaru, Jiro remains isolated. Meeting a high school student named Saburo Kazeda, Jiro briefly succumbs to the chip's residual influence, attacking him. Saburo transforms into the superhero Inazuman, leading to a battle. During this fight, Jiro finally breaks free from the chip's control. He saves Inazuman from an external threat, reconciles, and departs once more. While uncertain of his future path, he expresses tentative hope that he might eventually return to the Komyoji family.

Throughout his existence, Jiro evolves from a confused, childlike machine into a being burdened by complex emotions, ethical dilemmas, and the consequences of violence. His journey is defined by the tension between his programmed purpose, his desire for human connection, and the incomplete system within him that simultaneously grants profound empathy and makes him vulnerable to corruption. He ultimately accepts his dual nature – neither fully machine nor human – while continuing to seek peace and redemption.