Movie
Description
Dr. Sewashi is a scientist working at the Photon Power Laboratory whose career in robotics and energy research spans decades, beginning from his time as an apprentice under the legendary Professor Juzo Kabuto. Alongside his fellow apprentices and future colleagues, Dr. Morimori and Dr. Nossori, Sewashi continued his work at the laboratory under the direction of Professor Gennosuke Yumi, eventually becoming one of the key technical staff responsible for the development and maintenance of the super-robot Mazinger Z.

Physically, Dr. Sewashi is the tallest of the three scientists, with a lean frame, a bald head, bushy mutton chop sideburns, thick eyebrows, and a pair of oval-shaped glasses that contribute to his distinctive and somewhat eccentric appearance. Among his two companions, he is often seen as a leader figure, and his personality, while generally good-natured and patient, carries a slightly more impatient edge compared to his slower-paced colleague Dr. Nossori. The trio as a whole often serves as a source of comic relief, balancing their highly focused professionalism under pressure with lighthearted and occasionally goofy behavior in their downtime, including a shared but notoriously unskilled hobby of bowling. However, when an emergency arises or a technical crisis threatens the laboratory, this easygoing demeanor gives way to sharp problem-solving and determined action, demonstrating their deep commitment to their work and the protection of the Photon Power Laboratory.

Dr. Sewashi specializes in engine design, a specific area of expertise that complements his colleagues' focuses on metallurgy and energy studies. This technical specialization makes him an indispensable member of the team, as his innovations directly contribute to the combat capabilities of Mazinger Z. For instance, he engineered a reinforced pilot suit designed to enhance the performance of the robot's pilot, Koji Kabuto. His primary motivation is a deep-seated passion for research and a dedication to collaborative problem-solving, driven by a desire to support the robot's pilots in their fight against the forces of evil. This motivation is rooted in his history; having been a student of Juzo Kabuto, he carries on the legacy of using science and technology to protect humanity.

Within the story of Mazinger Z: Infinity, Dr. Sewashi continues to serve as a vital support member of the Photon Power Laboratory. When the titular giant robot, Infinity, is excavated and poses a new global threat, Sewashi and his long-time colleague Dr. Nossori collaborate on a crucial project. They deploy a revolutionary photonic energy three-dimensional printer, a device that uses the laboratory's photonic power to restore and later enhance the aging Mazinger Z, preparing it for a climactic confrontation with the revived Dr. Hell. In this film, the trio also assists in naming the mysterious android known as Lisa, with Sewashi and his colleagues coining the designation as an acronym for Large Intelligence System Agent. The presence of his old colleague Dr. Morimori is felt only through a portrait, a reference to the latter's death in the original television series, a loss that has only deepened the resolve of the surviving scientists.

The key relationships in Sewashi's life are almost entirely professional, centered on his two fellow scientists. The trio, often collectively referred to as the Three Scientists, functions as a single, highly efficient unit, relying on decades of shared history and mutual trust to improvise solutions under extreme conditions. Their camaraderie is so well-known that it has been exploited by enemies in the past, though such schemes were ultimately thwarted. His interactions with other main characters, such as pilots Koji Kabuto and Sayaka Yumi, are therefore typically in a subordinate technical capacity, taking orders from Professor Yumi and working tirelessly to ensure the robots are operational for battle. Over the course of the series and into the Infinity film, Dr. Sewashi does not experience a significant personal transformation; his development is instead shown through his enduring resilience and his continuous, unglamorous, but absolutely critical work behind the scenes. His notable abilities, beyond his core expertise in engine design, include a remarkable talent for quick thinking and inventing makeshift technological solutions during active combat situations, as well as the capacity to coordinate diversionary tactics to aid the heroes' missions. While his history outside the laboratory remains largely unexplored, his technical contributions continue across multiple projects, cementing his legacy as a steadfast innovator focused purely on team-oriented objectives.