都市伝説（としでんせつ）
Toshi densetsu
Urban legend: the rumours that spread through schools and media from the 1970s.
Toshi densetsu translates the American term urban legend, which reached Japanese folklore studies in the 1980s. The thing it names is older. In the spring and summer of 1979 the story of the slit-mouthed woman ran from Gifu through every prefecture in weeks, carried by children and then by newspapers and television, and the police took reports. In 1989 and 1990 the human-faced dog did the same.
What marks these stories is that they are told as news, about the teller’s own town, and that each place adds a detail: a favourite sweet that calms the woman, a dog that asks to be left alone. The prophesying calf of the 1836 broadsheet shows the pattern before there were cities to name it after.
Related yokai
Kuchisake-onna
口裂け女（くちさけおんな）
Kuchisake-onna is not an old yokai. She is a rumour that swept through Japanese schoolchildren in 1978–79: a masked woman asking 'Am I pretty?' Almost every other detail changed from school to school.
Jinmenken
人面犬（じんめんけん）
Jinmenken, the dog with a human face, swept through Japanese children's rumour around 1989–90. A first-grader in Yamagata had his own version: the dog had left Tokyo because people would not stop talking about it.
Teke Teke
テケテケ
Teke Teke is a modern school ghost story, best known as the upper half of a woman who drags herself along on her elbows. Its origin cannot be traced, and one recorded version from a Kobe high school puts it in a mirror instead.
Kudan
件（くだん）
An 1836 broadsheet from Tango described a kudan — a cow's body with a human face — and promised that any house that put up its picture would prosper. Other kudan of the same century foretold disaster instead.