Kiyoshi Mitarai

Kiyoshi Mitarai, also known as Seaman, 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 believes that all humans are inherently evil and simply require the chance to show it. (Wiki)