Kuchisake-onna（くちさけおんな）

The 1979 outbreak timeline. Kuchisake-onna fundamentally differs from Edo-period yokai. Its 7-month progression from the initial appearance (Gifu Nichinichi Shimbun's "Editor's Notes", January 26, 1979)^[1] to its subsidence (start of summer vacation in August) can be precisely tracked through newspapers, weekly magazines, and police records. In early December 1978, in Shinsei-cho, Motosu-gun, Gifu Prefecture, an elderly farmer woman went to the toilet detached from the main house, saw Kuchisake-onna, and collapsed from fear—this is recorded as the prototype rumor (according to Etsuro Hiraizumi's article in the June 29, 1979 issue of Shukan Asahi). National magazines repeatedly amplified it over half a year: Teruo Kanauchi's article in the March 23 Shukan Asahi, the June 29 large feature, July 3 Shukan Josei, July 5 Josei Jishin, and the December 31 Shukan Asahi year-end review. By June, it had conquered the country from Gifu to Aomori and Kagoshima. In August, when schools and cram schools entered summer vacation, the communication network of word-of-mouth among children was severed, and the rumor rapidly subsided. This exhibits a structural undulation unique to modern yokai: covering the entire country in half a year and disappearing in another half a year, which is inconceivable for simple Edo-period oral yokai.

The formula of dialogue and attack. "Am I pretty?" -> (If answered "pretty") Takes off the mask and asks "Even like this?" -> (If answered negatively) Attacks with scissors, a kitchen knife, sickle, or carving knife—this pattern of dialogue is recorded as the nationwide common core. There are various countermeasures: giving ambiguous answers like "average" or saying "beautiful inside and out". The most widespread item-based countermeasure is chanting "pomade" 3 times (or 6 times), writing it on the palm or sole, or throwing a bottle of it—this was later explained by a retroactive backstory that the surgeon who botched her plastic surgery wore a lot of pomade, whose smell she despised. Other regional variations include offering bekko ame (hard candy) (with both theories of it being her favorite and least favorite coexisting), chanting "garlic", writing "dog" on the palm, or escaping into a building on the second floor or higher (as she supposedly only pursues on the ground). Her moving speed is most commonly "runs 100 meters in 6 seconds", with variants like "3 seconds" or "3-meter jumps". The typical appearance is a red beret, red clothes, red high heels, a mask, and long hair. These stereotypes were rapidly standardized among elementary and junior high school students nationwide through newspaper reports and weekly magazine features—a typical example of a modern bizarre phenomenon where word-of-mouth and mass media resonate with each other.

Lineage of origin theories: The diversity of retroactive explanations. The Gifu Nichinichi Shimbun^[1] initial article has no explanation of origins, only stating the fact of "rumors among Gifu children". During the diffusion process, multiple origin theories attached retroactively: 1) The botched plastic surgery theory (a sociological reinterpretation against the backdrop of the 1970s cosmetic surgery boom), 2) The three sisters theory (all three have slit mouths, with variants of the origin being botched surgery, traffic accidents, or jealousy), 3) The theory of a reconstructed skull found in the Hida River bus crash (August 18, 1968), 4) The theory of an escapee from a mental hospital in Minokamo City, Gifu Prefecture in 1977-78, 5) The grudge of the Gujo Uprising (1754)—all of these are hearsay at the stage of "there is a theory that...", without any primary sources. The flow of "fact -> expansion -> standardization" is a common path in the generation of modern yokai post-war, showing a construction mechanism unique to the mass media age, different from Edo-period tsukumogami (desktop yokai assembled by Toriyama Sekien from literature and wordplay) and local folklore (bizarre tales picked up by Kunio Yanagita's folklore studies from oral traditions).

Prehistory of Edo-period slit-mouthed women: The boundary between continuity and independence. The motif of "a woman whose mouth is slit to her ears" exists in multiple Edo-period documents, forming an ancient layer independent of the 1979 phenomenon. The Edo-period ghost story collection "Kaidan Oi no Tsue"^[4] contains an episode in Okubo Hyakunincho (present-day Shinjuku, Tokyo) where an umbrella man calls out to a woman to share his umbrella, and when she turns around, her mouth is slit to her ears, said to be a fox disguise. The Edo-period reading book "Ehon Sayo Shigure" tells of a customer jokingly stopping a tayu in the Yoshiwara red-light district, only to see her mouth slit to her ears when she turns around; "Shin Chomonju" records the wife of Nakabashi's Takano Shozaemon putting her fingers in her mouth and tearing it to her ears, her hair standing on end, turning into a female demon and attacking her husband. As a Meiji-period example, there is a legend of Otsuya in Shigaraki, Shiga Prefecture, who dressed in white with white powder, messy hair, a candle on her head, holding a carrot cut into a crescent moon shape in her mouth and a sickle, crossing the mountain pass to meet her lover, which is sometimes cited as a model for the 1979 Kuchisake-onna (primary sources need tracing). However, modern folklorists like Toru Joko^[3] and Yoshiyuki Iikura predominantly read the 1979 phenomenon as an independent post-war phenomenon rather than a continuum with the Edo-period slit-mouthed women. It is academically honest to organize it as: the Edo-period traditions merely wait in the ancient layer as an archetype, while the 1979 incident was re-generated under post-war specific conditions of cram schools, national magazines, the plastic surgery boom, and nuclear families.

Interpretations from folklore and sociology. Toru Joko's "School Ghost Stories" (1990)^[3] systematized school ghost stories including Kuchisake-onna based on field interviews, pioneering the methodological treatment of modern children's culture, rumors, and ghost stories in folklore. Yoshiyuki Iikura of Kokugakuin University (oral literature, modern folklore) points out cram schools as the medium of transmission—post-war cram schools created places where children gathered across school districts, serving as a catalyst for word-of-mouth diffusion before mass media. A sociological reading is shared in multiple secondary sources: post-war nuclear families + dual-income households + women's advancement in society + the cosmetic surgery boom created anxiety over the absence of mothers, anxiety over "beauty", and fear of "beautiful women who had plastic surgery", which were projected onto the image of Kuchisake-onna. The fact that Shigeru Mizuki's "Illustrated Encyclopedia of Japanese Yokai" (1991)^[5] included Kuchisake-onna as an item is often pointed out as a symbolic moment when "modern bizarre phenomena were formally incorporated into the framework of yokai."

Media developments: Post-war yokai living on in film and manga. As a contemporaneous television reaction, a monster modeled after Kuchisake-onna appeared in Episode 29 of "Battle Fever J" broadcast in 1979. The representative film adaptation is Koji Shiraishi's "Carved: The Slit-Mouthed Woman" (2007)^[6], a post-war horror film that tackled the 1979 phenomenon head-on. Sequels "Carved 2" (2008), "Kuchisake-onna Returns" (2012), "Kuchisake-onna in L.A." (2016), and the Japan-South Korea co-production "Ghost Mask: Scar" (2019, directed by Go Sone)^[7] attempted a cross-East Asian re-creation combining Korea's plastic surgery culture and Kuchisake-onna. In manga, Episode 31 of Shou Makura and Takeshi Okano's "Hell Teacher Nube" is a representative sympathetic reinterpretation, rewriting it as a story where Nube exorcises an animal spirit possessing her and restores her to her original beautiful figure, later introducing the three-sisters setting to reinforce the origin theory variants from the story's side. In South Korea, she became popular again in the 2000s as "Red Mask (빨간 마스크)", and Korea's unique variants based on blood types developed (A-types get a 1cm cut, O-types get their whole face slashed). In the English-speaking world, she is recognized as "Slit-Mouthed Woman" and introduced as a representative example of modern Japanese bizarre phenomena in overseas yokai introductory and academic books.

Academic positioning: The new framework of modern yokai and urban legends. Kuchisake-onna is positioned as a representative example of the new frameworks in post-war yokai studies: "modern yokai (modern bizarre phenomena)" and "urban legends". Around the time the concept of "urban legends" was introduced to Japan with the Japanese translation of American folklorist Jan Harold Brunvand's "The Vanishing Hitchhiker" in 1988, Toru Joko's "School Ghost Stories" (1990)^[3] incorporated school ghost stories into the targets of folklore field research, and since the 2000s, analysis from sociology, media studies, and cultural studies has been added, with Yoshiyuki Iikura and others reading it as a mode of "yokai generation in the mass media age". Alongside Edo-period oral yokai, Toriyama Sekien's desktop tsukumogami, and modern folklore's local collections, Kuchisake-onna is an entity that expanded the framework of yokai research as a paradigm of "the mechanism of yokai generation unique to the post-war mass media age".