A concept given to the telling of scary stories, folktales and urban legends.
In Japan telling ghost stories is usually a thing of tradition especially during festivals such as O-bon. O-bon is the annual festival for celebrating one's ancestors which takes place during the summer (the dates for O-bon differ from temple to temple) during that time people tell frightening ghost stories about them.
There is also the 100 Ghost Story game which was a popular parlor game called Hyakumonogatari Kaidankai, from the Edo period (1603 - 1868). The rules were as follow:
Many people believe that the extinguishing of the last candle represents the conclusion of a spiritual evocation, summoning some supernatural being from another world. Many believe that the ceremony was a test of courage among the samurai, which later became a game used by common folks to scare each other.