Legend has it that "every year the yokai Nurarihyon, will lead all of the yōkai through the streets of Japan during summer nights." Anyone who comes across the procession would perish or be spirited away by the yōkai, unless protected by handwritten scrolls by anti-yokai onmyoji spellcasters. It is said that only an onmyoji clan head is strong enough to pass Nurarihyon's Hyakki Yagyo unharmed.
According to the account in the Shūgaishō (拾芥抄), a medieval Japanese encyclopedia, the only way to be kept safe from the night parade if it were to come by your house is to stay inside on the specific nights associated with the Chinese zodiac or to chant the magic spell: "KA-TA-SHI-HA-YA, E-KA-SE-NI-KU-RI-NI, TA-ME-RU-SA-KE, TE-E-HI, A-SHI-E-HI, WA-RE-SHI-KO-NI-KE-RI" (カタシハヤ, エカセニクリニ, タメルサケ, テエヒ, アシエヒ, ワレシコニケリ).
The hyakki yagyō has appeared in several tales collected by Japanese folklorists.
- Uji shui Monogatari (宇治拾遺物語), in which a monk encounters a group of a hundred youkai which pass by the Ryūsenji temple.
- Konjaku Monogatari Shuu (今昔物語集), which tells that during the Jougan Era (859–877), the eldest son of minister Fujiwara was on his way to his lover's place when he saw 100 demons walking from the direction of the University of Tokyo Miya main street. Since his attire had the sonjoushi written on it, the demons who noticed this ran away.
- The Great Mirror(大鏡, Ookagami)
- Goudanshou (江談抄)
- Kohonsetsuwashuu (古本説話集)
- Houbutsushuu (宝物集)
The night parade was a popular theme in Japanese visual art.
One of the oldest and most famous examples is the 16th-century handscroll Hyakki Yagyō Zu (百鬼夜行図), erroneously attributed to Tosa Mitsunobu, located in the Shinju-an of Daitoku-ji, Kyoto. For other picture scrolls, the Hyakki Yagyō Emaki (百鬼夜行絵巻), contains the details of each member in the parade from the Muromachi period.
Other notable works in this motif include those by Toriyama Sekien (Gazu Hyakki Yagyō) and Utagawa Yoshiiku. However, Toriyama's work presents yokai in separate, encyclopedic entries rather than assembled in a parade, while Utagawa's Kokkei Wanisshi-ki ("Comical Record of Japanese History") employs the theme of 100 demons to comment on contemporary Japanese military actions in China.
- Nurarihyon no Mago
- Gazu Hyakki Yagyō
- Gazu Hyakki Tsurezure Bukuro
- Konjaku Gazu Zoku Hyakki
- Konjaku Hyakki Shūi
- Unseelie Court
- Wild Hunt
- Clark, Timothy (1993). Demon of Painting: The Art of Kawanabe Kyosai. British Museum Press. p. 64. ISBN 0714114626.
- Lillehoj, Elizabeth (1995). "Transfiguration: Man-Made Objects as Demons in Japanese Scrolls". Asian Folklore Studies. 54 (1): 7–34. doi:10.2307/1178217. JSTOR 1178217.
- 村上健司編著 『妖怪事典』毎日新聞社、2000年、288-289頁。ISBN 4-620-31428-5。
- "Hyakki Yagyō". Retrieved 2014-05-19.
- Foster, Michael Dylan (2009). Pandemonium and Parade: Japanese Demonology and the Culture of the Yōkai. University of California Press. p. 55.
- Lillehoj, Elizabeth. "Commentary". The Boone Collection. Retrieved 8 April 2013.