Nurarihyon

Nurarihyon is a kaii typically portrayed as an elderly man with an enormous hairless head, wearing a hunting robe. Transmitted as a sea-spirit entity—akin to the kaiyōbōzu (sea monks)—in legends from Okayama and Kagawa Prefectures along the Seto Inland Sea, it also appears in early modern picture scrolls as a figure of authority among yokai. The woodblock illustration by Toriyama Sekien in *Gazu Hyakki Yagyō* (1776) became widely known.

In the original Okayama and Seto Inland Sea traditions, the being was recorded as a large round head floating on the water—"nuurihyon" or "nurarihyon"—a kaiyōbōzu-type entity that would slip away if one attempted to capture it. In picture scrolls, by contrast, it took an anthropomorphic form: an unnamed elderly man who would enter a house in the master's absence, drink tea uninvited, and take his ease. From the modern period onward, a popular interpretation emerged of nurarihyon as the supreme leader of yokai.

The Okayama tradition traces to oral accounts associated with the early modern regional gazetteer *Bizen-no-Kuni Fudoki*, recorded as a kaiyōbōzu or kainyūdō (sea-entering monk) type phenomenon. Representative picture-scroll depictions include Sawaki Takeyoshi's *Hyakkai Zukai* (1737) and Toriyama Sekien's *Gazu Hyakki Yagyō*. Modern scholarship appears in works such as Kyogoku Natsuhiko and Tada Katsumi's *Yōkai Zukan*, Murakami Kenji's *Nihon Yōkai Daijiten*, and Yumoto Koichi's *Nihon Yōkai Zufu*.

In the Seto Inland Sea, nurarihyon as a sea-appearing entity belongs to a constellation of related legends alongside takonyūdō (octopus monks), kaiyōbōzu, and funiyūrei (ship ghosts). The picture-scroll depiction as an elderly man was reinterpreted in modern and contemporary manga and anime—notably Mizuki Shigeru's *Gegege no Kitarō*—as the supreme commander of yokai, circulating widely in a context distinct from the Okayama sea-spirit traditions.