Kijo of Kurozuka.

The Kijo of Kurozuka appears as a shriveled old woman with wild hair, a huge mouth, and the capacity to shift from pitiable solitude to murderous ferocity. In many tellings she first looks like a harmless old hostess in a hut or cave. The horror arrives when her hidden nature is revealed by bones, bloodstains, or the forbidden inner chamber she tries to keep guests from seeing.

Her signature interaction is false shelter. A traveler, monk, or priest is offered lodging on the moor, asked to obey a simple prohibition, and then discovers that the place is full of human remains. Once exposed, the old woman becomes an onibaba and gives chase. In Noh and later retellings, the scene turns on loneliness, taboo, and the instant when compassion curdles into predation.

The legend is tied to Adachigahara in Mutsu and the mound called Kurozuka, but its exact origin is unstable. Some versions make the demon woman a transformed human driven mad by crime and grief, while others treat her as an already demonic being haunting the region. What remains constant is the setting: a bleak frontier landscape where hospitality is uncertain and Buddhist prayer becomes the line between human survival and devouring wilderness.