ONA
Description
Professor Ochanomizu is a senior scientist in the world of Pluto who serves as the head of Japan's Ministry of Science, a post he assumed after Professor Tenma, the creator of Atom. He is a widower who lives alone in the downtown area of Tokyo, and he has become the foster parent and primary guardian of Atom and his sister robot Uran. Before the main events of the story, he took part in the Bora survey mission, an international investigation into suspicions that the Kingdom of Persia was manufacturing weapons-grade robots, and this involvement ties him directly to the larger political and criminal conspiracy that drives the plot.

In personality, Ochanomizu is defined by a strong sense of justice and a liberal outlook that treats robots as fully equal to humans, holding no prejudice against them at a time when public fear of robot violence is rising. He is warm, good-natured, and deeply nurturing, and he is widely regarded as a beloved grandfather figure to the robots in his care. He is also somewhat absent-minded and easily moved to tears, but beneath this gentle exterior he is a principled and dependable figure whose moral convictions give him quiet strength during crises.

His central motivation is the protection and wellbeing of Atom and Uran, whom he cherishes as though they were his own children. More broadly, he is driven by the belief that science should serve life rather than destroy it, and he works to uphold the laws and values that allow humans and robots to coexist peacefully. He opposes the misuse of advanced robotics for warfare and is committed to uncovering the truth behind the murders of the world's most powerful robots, even when doing so puts him in personal danger.

Within the story, Ochanomizu functions as Atom's mentor, confidant, and moral anchor. His home serves as a refuge for the young robot, and he provides guidance whenever Atom struggles with questions of emotion, identity, and duty. He also acts as a bridge between the scientific community and the authorities investigating the robot murders, lending his expertise and credibility to the search for answers. His past participation in the Bora survey gives him knowledge of the events that set the tragedy in motion, making him a significant figure in the investigation even though he operates largely behind the scenes.

His most important relationships are with his surrogate children. With Atom, he is a patient father figure and the person Atom turns to for advice and reassurance; with Uran, he is a caring guardian. His relationship with Professor Tenma is marked by contrast, since Tenma abandoned Atom after failing to see him as a replacement for his dead son, while Ochanomizu accepts and loves Atom unconditionally. He also works alongside other scientists and cooperates with robot investigators such as Gesicht, and his reputation as a fair and compassionate leader earns him the trust of robots across the world.

Over the course of the story, Ochanomizu's peaceful beliefs are tested as the killings escalate and as hatred between humans and robots intensifies. He responds not by retreating into fear but by reaffirming his commitment to coexistence, and his resolve becomes increasingly important as a counterweight to the cynicism and despair around him. His development is less about personal transformation and more about endurance: he remains a steady, ethical presence whose care for Atom and Uran never falters even as the world around him becomes more dangerous.

As for abilities, Ochanomizu is not a fighter, and his strength lies in intellect and authority rather than physical power. As head of the Ministry of Science he holds considerable administrative influence, giving him access to government resources, oversight of robot-related policy, and connections with leading scientists worldwide. His extensive knowledge of robotics allows him to analyze events that others cannot fully explain, and his experience in international investigation makes him a shrewd observer of the political maneuvering surrounding the robot case. His most notable qualities, however, are his moral clarity and his capacity for compassion, which quietly shape the actions of those around him throughout the story.