Kiyoshi Mitarai (御手洗 清志, Mitarai Kiyoshi), also known as Seaman (水兵(シーマン), is a human who develops superhuman powers as a result of the demon plane hole opened by Sensui. He is able to mix his blood with water to create water golems. His territory is contained within these monsters. Mitarai is emotionally scarred after watching the Black Chapter. He also is fueled by his hatred of bullies since he never seemed to have any friends. He believes that all humans are inherently evil and simply require the chance to show it. After being defeated by Kuwabara, Mitarai rethinks his stance on humans and decides to help in the fight against Sensui. After the fight with Sensui, he lives a normal life and gets into the best high school in the city. In the anime television series, Mitarai is voiced by Rika Matsumoto in Japanese and Justin Pate in English.