Tradition: Japanese Mythology
Alternative Names: Furuyanmori, Furuyanoboru, Ameyanmori, Muru, Morudo, Furuzomoruzo
Category: House dweller
The Myth
Furuya no Mori is a mysterious and terrifying entity in a widely known Japanese folktale. Its name literally refers to a leak in an old house, where rainwater drips through a damaged roof. Although it is not necessarily a real monster within the story, its name becomes so frightening that even dangerous animals and thieves believe it must be a terrifying supernatural being.
The tale begins on a rainy night, when an old man and woman are resting in their house. A ferocious animal, often described as a tiger or wolf, enters the area intending to steal or attack their livestock. A thief also sneaks into the house, hoping to take advantage of the darkness. Inside, the old couple complain about the Furuya no Mori, speaking as though it is far more frightening than tigers and wolves and lamenting that it has come again that night.
The animal overhears their conversation and becomes terrified. Believing that a creature more powerful and dangerous than itself must be nearby, it trembles in fear. At the same moment, the startled thief falls from the ceiling onto the animal’s back. The animal assumes that the thief is the dreaded Furuya no Mori and bolts away at full speed, carrying the terrified thief with it.
Eventually, the thief manages to escape from the animal but falls into a deep hole from which he cannot climb. A monkey comes to investigate and lowers its long tail into the hole. The thief grabs the tail, hoping to pull himself out, but he clings so tightly that the monkey’s tail breaks. According to this version of the story, this explains why monkeys have short tails.
The details vary between regional versions. The animal that fears Furuya no Mori may be a tiger, wolf, wild boar, badger, or baboon. Some versions feature a supernatural creature such as Yamajiji, while others use imaginary animal names resembling combinations such as “tiger-wolf” or “lion-wolf.” When the story features a tiger, an animal not native to Japan, some versions explain its presence by placing the story in China or Korea, or claim that tigers once fled Japan because they were frightened of Furuya no Mori.
The entity’s name also changes according to local dialects. Many alternatives refer to a leaking roof in an old house, while some stories leave its nature vague, describing it simply as something terrifying. In other versions, the tiger or thief explicitly mistakes the supposed entity for a monster. One unusual variant from Taki District in Hyōgo Prefecture replaces the mysterious leak with a persimmon: a crying child is threatened with being eaten by a tiger, but when the child stops crying after receiving a persimmon, the tiger becomes frightened of the fruit, believing it to be more terrifying than itself.
Furuya no Mori is an example of a folktale in which fear arises from misunderstanding rather than from an actual monster. The old couple are referring to an ordinary household problem, but the intruders interpret their words as evidence of a terrible creature. The resulting confusion turns a harmless leak into a source of supernatural terror. The tale has been widely transmitted throughout Japan, with a written version recorded in the 1768 collection Kidan Isshō under the title Yarou Kai. Similar stories involving frightened animals, mistaken identities, and thieves caught in the confusion are also found in China, Korea, Mongolia, India, and elsewhere.
Sources
“Furuya no Mori.” 新版TYZ 妖怪図鑑 (New TYZ Yokai Encyclopedia). https://tyz-yokai.blog.jp/archives/1074589384.html