The zashiki-warashi, or guest room child, are a type of yokai that appear in a Japanese fictional story, told mostly in the prefecture of Iwate. They are yokai who are thought to live in storage rooms, called “zashiki” in Japanese, and the purpose of their presence is to perform pranks. Yokai are not visible to the naked human eye, and normally a great amount of spiritual energy needs to be present, or there needs to be some kind of special circumstance in order for yokai to be present, but a person who manages to see a zashiki warashi is thought to be met with fortune after meeting them.
Zashiki warashi generally appear in the form of a child, with a reddish face and cropped or short bobbed hair that hangs down, not tied. They like to do pranks, such as leaving bleaching powder or ash in corridors of the house they settle in at night to make it appear like footsteps, as if some spirit had walked around the place.
Since zashiki warashi are thought to bring good fortune to the houses they inhabit, the families in those houses treat these yokai accordingly. Many families wish to see themselves going in a good direction, so they will treat the yokai hospitably, offering meals and treats to it everyday.
The legend of zashiki warashi is believed to have originated during harsh times. In the Tohoku region of Japan, there have been numerous cases of infanticide in families that could not afford to feed their babies. The babies would be crushed to death with a stone and buried in a dirt floor room. Their spirits were believed to later haunt those rooms and houses.
Today the zashiki warashi is a popular creature and references throughout pop culture, appearing in comics and anime.