Ninngyo

It is the Yokai whose lower is a figure of a fish.

It appear in Europe and all over the world, but is seen over a wide area in Japan.
It likes pure water and appears in lakes and a ponds.
The thing, which seemed to be a mermaid, appeared in country of Oomi, Gamochou, a record stays in the Japan Chronicle of Japan.

A mermaid is female and appears before human beings while sitting down on a rock on the seaside and singing a song in a beautiful voice. It is said that they tempt a passing men and drag them into the sea. Their figures are very beautiful, and it is said that storms and disasters are caused when mermaids appears. On the other hand, a male mermaid called a Merman, and has a bad, and, as the thing which represents a storm, it is said that its figure is ugly. Merman rarely turn up in public. The real nature mermaids is said to be both like a dugong and a manatee.