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 appear under the skin , which seem to have a life of its own . Prick it with a needle , and it glide 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 was 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 .