Nurarihyon

Nurarihyon (Japanese: 滑瓢 or ぬらりひょん, meaning "slippery gourd") is a mysterious and powerful Yokai encountered all across Japan. He is sometimes called nūrihyon.

Myths & Legends
Nurarihyon shows up on evenings when a household is extremely busy. He arrives at homes unexpectedly in his splendid palanquin and slips into the house, unnoticed by anyone. He helps himself to the family's tea, tobacco, and other luxuries, acting in all respects as if he were the master of the house. His power is so great that even the real owners of the house, when they finally notice his presence, can do nothing to stop him. In fact, while he is there, the owners actually believe the nurarihyon to actually be the rightful master of the house. Eventually he leaves just as he came, quietly and politely slipping out of the house and into his palanquin, as the owners of the house obsequiously bow and wave him farewell. Only after he has left does anyone become suspicious of the mysterious old man who just visited.

Appearance
Appearances can be deceiving, and nurarihyon is the perfect illustration of that saying. Overall, he is rather benign-looking, his head elongated and gourd-shaped. His face is wizened and wrinkled, resembling a cross between and old man and a catfish. He wears elegant clothing – often a splendid silk kimono or the rich robes of a Buddhist abbot – and carries himself in the quiet manner of a sophisticated gentleman.

Behavior
The short, comical, elderly nurarihyon is actually the most powerful and elite of all the yokai in the world. He travels in an ornate palanquin carried by human or yokai servants, often visiting red light districts, but occasionally stopping at mountain villas as well. He is known as “the Supreme Commander of All Monsters,” and every yokai listens to his words and pays him respect, treating him as the elder and leader in all yokai meetings. Along with Otoroshi and Nozuchi, nurarihyon leads the procession known as the "night parade of one hundred demons" through the streets of Japan on dark, rainy nights. He fits the role of supreme commander every bit as much when he interacts with humans as well.

Origin
As to nurarihyon’s origins there is only speculation, for the oldest records of his existence are mere sketches and paintings. His name connotes a slippery evasiveness – which he employs when posing as master of the house. Its name comes from “nurari” (to slip away) and “hyon” (an onomatopoeia describing floating upwards) written with the kanji for gourd (due to the shape of his head).

In Okayama, some evidence exists linking nurarihyon to umi-bōzu. There, nurarihyon are globe-shaped sea creatures, about the size of a mans head, which float about in the Seto Inland Sea. When fisherman try to catch one, the sphere sinks down into the water just out reach and then bobs back up mockingly. It has been theorized that some of these slippery globes migrate to land, where they gradually gain influence and power, becoming the nurarihyon known throughout the rest of Japan. Whether this theory is the true origin of the Supreme Commander of All Monsters or just one more of his many mysteries is yet to be solved.