Some random info on foxes from the Wiki
"Kitsune are believed to possess superior intelligence, long life, and magical powers. They are a type of yōkai, or spiritual entity, and the word kitsune is often translated as fox spirit. However, this does not mean that kitsune are ghosts, nor that they are fundamentally different from regular foxes. Because the word spirit is used to reflect a state of knowledge or enlightenment, all long-lived foxes gain supernatural abilities.
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Physically, kitsune are noted for having as many as nine tails.[12] Generally, a greater number of tails indicates an older and more powerful fox; in fact, some folktales say that a fox will only grow additional tails after it has lived 1,000 years.[13] One, five, seven, and nine tails are the most common numbers in folk stories.[14] When a kitsune gains its ninth tail, its fur becomes white or gold.[12] These kyūbi no kitsune (九尾の狐 ?, nine-tailed foxes) gain the abilities to see and hear anything happening anywhere in the world. Other tales attribute them infinite wisdom
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A kitsune may take on human form, an ability learned when it reaches a certain age — usually 100 years, although some tales say 50.[13] As a common prerequisite for the transformation, the fox must place reeds, a broad leaf, or a skull over its head.[16] Common forms assumed by kitsune include beautiful women, young girls, or elderly men. These shapes are not limited by the fox's age or gender,[4] and a kitsune can duplicate the appearance of a specific person.[17] Foxes are particularly renowned for impersonating beautiful women. Common belief in medieval Japan was that any woman encountered alone, especially at dusk or night, could be a fox.[18]
In some stories, kitsune have difficulty hiding their tails when they take human form; looking for the tail, perhaps when the fox gets drunk or careless, is a common method of discerning the creature's true nature.[19] Variants on the theme have the kitsune retain other foxlike traits, such as a coating of fine hair, a fox-shaped shadow, or a reflection that shows its true form.[20] Kitsune-gao or fox-faced refers to human females who have a narrow face with close-set eyes, thin eyebrows, and high cheekbones. Traditionally, this facial structure is considered attractive, and some tales ascribe it to foxes in human form.[21] Kitsune have a fear and hatred of dogs even while in human form, and some become so rattled by the presence of dogs that they revert to the shape of a fox and flee. A particularly devout individual may be able to see through a fox's disguise automatically.[22]"


"Kitsunetsuki (狐憑き or 狐付き; also written kitsune-tsuki) literally means the state of being possessed by a fox. The victim is always a young woman, whom the fox enters beneath her fingernails or through her breasts.[27]In some cases, the victims' facial expressions are said to change in such a way that they resemble those of a fox. Japanese tradition holds that fox possession can cause illiterate victims to temporarily gain the ability to read.[28] Though foxes in Folklore can possess a person of their own will, Kitsunetsuki is often attributed to the malign intents of a hereditary fox employers, or tsukimono-suji.[29]
Folklorist Lafcadio Hearn describes the condition in the first volume of his Glimpses of Unfamiliar Japan:
Strange is the madness of those into whom demon foxes enter. Sometimes they run naked shouting through the streets. Sometimes they lie down and froth at the mouth, and yelp as a fox yelps. And on some part of the body of the possessed a moving lump appears under the skin, which seems to have a life of its own. Prick it with a needle, and it glides instantly to another place. By no grasp can it be so tightly compressed by a strong hand that it will not slip from under the fingers. Possessed folk are also said to speak and write languages of which they were totally ignorant prior to possession. They eat only what foxes are believed to like — tofu, aburagé, azukimeshi, etc. — and they eat a great deal, alleging that not they, but the possessing foxes, are hungry.[30]
He goes on to note that, once freed from the possession, the victim will never again be able to eat tofu, azukimeshi, or other foods favored by foxes." - Not the tofu!