Kappa

In Medieval Japan, a breed of humanoid creature called the Kappa was believed at the time to dwell in rivers and swampy areas.
It was a type of vampirelike lecherous creature that is more intelligent than the devilish, and less malevolent toward men.

They walked erect, though their extremities ended in webbed structures that looked not unlike claws. There hung down from their large mo­bile ears weird appendages resembling long narrow earrings. Their eyes were triangular and elongated, while on the top of the head there sat what appeared to some observers to be a bald spot, to others a big ball of yarn out of which stuck four lengthy darning needles.
Whatever the case may be, legends have grown up around them suggesting that they are dirty; greedy and lazy-very much like some of the "wee folk" of the Celtic legends.

They are, however, extremely polite. So here is what you do: you will recognize a Kappa from the bowl-like depression on top of its head filled with water. This is its power source.

So you bow to a KAPPA in the approved Japanese fashion, and naturally having to return the courtesy it will bow back and the water tips out. It is then powerless until the water can be replenished.

This is not all. They are crazy about cucumbers. They prefer cucumbers to blood. Bribe them with a cucumber and they will promise you almost anything. And once a promise is made they are honor-bound to keep it.

Ama-no-Iwato, the Heavenly Rock Cave

After heaven and earth had been separated, two married kami, Izanagi-no-kami and Izanami-no-kami, gave birth to the land of Japan and to various kami of the seas, the rivers, the mountains and the fields. Finally the two gave birth to three specially revered kami: Amaterasu Omikami, Tsukiyomi-no-kami and Susanoo-no-kami. They gave necklace of jewel beads to Amaterasu Omikami and ordered her to govern Takama-no-Hara (the Plain of Heaven), they further ordered Tsukiyomi-no-kami to govern the night and Susanoo-no-kami to govern the sea. Susanoo-no-kami, however, went against the will of the married deities and gave up governing the sea. Instead he ascended to Takama-no-Hara, and committed outrageous deeds such as destroying the paddy fields and the weaving house on the Heavenly Plain. Amaterasu Omikami angered by his behavior and hid herself in the Heavenly Rock Cave called Ama-no-Iwato. As a result, the world of both heaven and earth became dark, throwing everything into confusion. The eight million kami got together beside the river in the Plain of Heaven, debating how to induce Amaterasu Omikami to come out of the Heavenly Rock Cave. They decided first to make the divine mirror Yata-no-Kagami and hang it in front of the cave, second, to hold a joyous festival, and third, to perform the sacred dance and music called kagura. As a result of this, Amaterasu Omikami emerged from the Heavenly Rock Cave, illuminating everything with her gentle light. She made heaven and earth bright again and brought back harmony and order. Susanoo-no-kami was expelled from the Heavenly Plain to the land of Izumo. There Susanoo-no-kami, killed a giant snake, the Yamata-no-Orochi, which had been tormenting the people of Izumo. He extracted a divine sword out of the snake's tail and presented it to Amaterasu Omikami. This sword is one of the three imperial regalia.