The Hyakki Yagyo, translated into English as "Night Parade of One Hundred Demons", is a massive night parade composed of a wide variety of Youkai — demons and spirits believed to be responsible for natural phenomenon of all kinds — where they party and generally cause chaos. It is often used as an idiom for riots and disorderly processions, though some believe it to be a real event in folklore.
Over the years, many different interpretations of how the Parade works have cropped up. Some believe it's led by the youkai Nurarihyon and that it's hosted every summer evening. Humans unprotected by exorcism charms or are not the Onmyoji clan head are killed in the chaos.
- Ayakashi Triangle shows a very benign form of hyakki-yakō while Kachofugetsu run laps for gym glass. Matsuri muses on if Yayo and Lu could see the supernatural, and has an Imagine Spot of many different types of ayakashi running alongside them (one of which is tripping).
- In the intro for Ghost Stories, silhouettes of several Youkai are seen parading down a dirt road, though this never actually appears in the show.
- In the universe of Jujutsu Kaisen, the "Night Parade of One Hundred Demons" was a terrorist attack organized by the sorcerer Suguru Geto, in pursuit of Rika Orimoto and Yuta Okkotsu. He had a multitude of demons swarm the cities of Shinjuku and Kyoto while students, faculty, and alumni of Jujutsu High were on hand to fight back.
- The phenomenon is referenced in Sengoku Youko, where the second protagonist Senya has the spirits of 1000 different youkai locked within him. One of his signature attacks is the "Senki Yagyo", named after the youkai he eventually tames within himself. The motif goes away after he reaches enlightenment, replaced with a Buddhist motif. Around the same time, the final antagonist group, the Tribe of the Void, has created its own Senki Yagyo, although it consists of all the demons being brainwashed to work for them.
- Touhou Suzunaan ~ Forbidden Scrollery: The Night Parade scroll has the ability to create tsukumogami, and an oni sealed inside it serves as the Final Boss of the manga due to it possessing Kosuzu.
- In one chapter/episode of xxxHolic, Yuko orders Watanuki and Doumeki to attend the lantern parade of youkai to get the special sweet nectar from the big tree. They were given a "ground cherry" lantern which they need to participate in the parade.
- Future Card Buddyfight: The antagonists of the second season are explicitly called the Hundred Demons, and their flag is Parade of Hundred Demons. True to their inspiration, they're responsible for the events that occur at that time.
- Gazu Hyakki Yagyo, or "The Illustrated Night Parade of a Hundred Demons", is the first illustrated book by in Toriyama Sekien's famous Gazu Hyakki Yagyo e-hon tetralogy, acting as an illustrated bestiary of Youkai.
- Masako Miki is a contemporary Japanese fine-artist who creates abstract drawings, paintings sculptures and furniture that is loosely based off of Youkai and other forms of Japanese folklore, including various ink and watercolor on paper illustration with names interchangeably referred to as Hyakki Yagyō (Night parade of One Hundred Demons), including Awakening During Sleep, Fox's Dream and Fox and Water Jugs.
- Operation: Specter in Pom Poko is a display of illusory magic practiced by the Tanuki elders of Shikoku that simulates a ghostly parade of youkai and demons as part of a last ditch attempt to protect Tama Hills from human development. Since the humans of New Tama are not as superstitious as those in Shinkoku, it winds up being confused for a festive piece of advertisement for a local theme-park company, made all the more insulting since one of the Elders wound up dying from the strain of it.
- The Parade in Paprika is a dream that induces madness in whoever gets it inspired by the Hyakki Yagyo, right down to invading the real world.
- While it is not stated outright, the plot of Spirited Away implies that this is occurring during the film's story. Chihiro and her parents end up trapped in the Spirit World when they stay at the abandoned amusement park before sunset, something that is commonly believed to happen to humans who happen upon the Hyakki Yagyo. The fact that it is set in an amusement park with a "restaurant row," in and out-going cruise ships and a fully-stocked bathhouse hints that this is occurring in the middle of a festival.
- The Girl With Ghost Eyes, set in San Francisco's Chinatown, features a similar parade early on (with its liminal aspects particularly plot-relevant). The author points to Chinese tradition for the parade's characteristics, but, for want of an authentic Chinese name for the whole thing, calques one from Japanese.
- The music video for Denki Groove's "Mononoke Dance" features a human couple getting pulled into a cross between the Hyakki Yagyo and a rave. While the girl has a great time dancing (and flirting) with the various monsters, the guy is a Butt-Monkey who's terrorized and bullied by all the youkai, and at one point gets press-ganged into turning a Wheel of Pain that powers the DJ's booth.
- Exalted: Referenced by the 3rd Edition bestiary, which is titled Hundred-Devils Night Parade.
- Forgotten Realms: "Night Parade" was a Second Edition module where monsters from the Demiplane of Nightmares plotted to infiltrate the Prime Material Plane and unleash their kin. The full size of the Night Parade was never revealed, but it was in the thousands.
- Monster Hunter: Rise: A central event in the story is a reoccurring catastrophe known as the "Rampage", where all the local monsters inexplicably go crazy and begin destroying everything in sight in a stampeding mob (later revealed to be caused by the mating cycle of two Elder Dragons, Ibushi and Narwa). Many of the new monsters also take heavy inspiration from Youkai and the specific setting is strongly Wutai based. The description on the Japanese website makes the comparison even more obvious by calling it "The Night March of One Hundred Wyverns".
- Oreshika: Tainted Bloodlines features the "Feast of All Demons", an event that happens once every in-game year, filled with many youkai that often drop good rewards. In order to advance the plot, you need to attend the event and defeat the boss there.
- Touhou: One of the oni Suika's Boss Subtitles is "Tiny Night Parade of One Hundred Demons". She can also split herself into multiple smaller versions of herself, make herself gigantic, and attract people to parties thanks to her power of controlling density (population density in the latter case).
- Appears in the Yo-Kai Watch franchise in the form of a randomly-triggered rhythm minigame, referred to in the English translation as the "Kaos March". In order to trigger it, the main character must walk around the Downtown Springdale area on a clear night, when the in-game clock is between 9 and 12 PM. There is a chance that he or she will stumble upon a group of marching Yo-kai that will invite him or her to join them. The player must move the stylus and tap the touch screen in sync with the music in order to win. Once the Kaos March has first been discovered, it can be triggered again by speaking to a certain NPC Yo-kai. It appears in both Yo-kai Watch 2 and Yo-kai Watch 3.
- In Erma, Erma's family are invited to Japan by her maternal relatives, the Yureimotos, to take part in the Night Parade. It is implied that while it is a fun party to be involved in, the sheer anarchy of it can be dangerous, hence why Fumiko objects to her father's idea to involve the servants for fear of their lives.