Reportedly observed on multiple occasions by crew members of government-operated "whale research" ships, these so-called "Ningen" (lit. "humans") are said to be completely white in color with an estimated length of 20 to 30 meters.Eyewitnesses describe them as having a human-like shape, often with legs, arms, and even five-fingered hands. Sometimes they are described as having fins or a large mermaid-like tail instead of legs. The only visible facial features are the eyes and mouth.
According to one account, crew members on deck observed what they initially thought was a foreign submarine in the distance. When they approached, however, it became clear from the irregular shape of the thing that it was not man-made -- it was alive. The creature quickly disappeared under water.