Kappa

The kappa (河童, "river-child") is a unique creature in Japanese folklore - a reptilian water deity that shares characteristics with yōkai spirits. Also known by names like kawatarō ("river-boy"), komahiki ("horse-puller"), and led by beings called kawatora ("river-tiger") or suiko ("water-tiger"), these beings demand respect to maintain their benevolent nature.

Typically portrayed as green humanoid creatures, kappa have webbed extremities and turtle-like shells on their backs. Their most distinctive feature is a water-filled depression on their heads called a sara ("dish") - if this reservoir is emptied or damaged, the kappa's power drastically diminishes.

These beings are known for their fondness for cucumbers and sumo wrestling. However, they also have a darker reputation for attacking humans in waterways and extracting a mythical organ called the shirikodama through rather unusual means.