He is described as short and young-looking. He is consistently shown with visible joints on his limbs. His belt is consistently portrayed as being green, and his boots are removable, revealing rather human-like feminine feet underneath. Kind and sweet, Astro is a robot modeled by a scientist named Dr. Tenma, modeled after Tenma's deceased son, Tobio, who was tragically killed in a car accident. Astro Boy is kindhearted and naive most of the time. A robot who can feel emotion, a very good fighter