The hyakki yakkou is the dreaded night parade of one hundred demons - the night when all of the yokai, oni, ghosts, tsukumogami, and other supernatural creatures leave their homes and parade through the streets of Japan in one massive spectacle of utter pandemonium. Those foolish enough to go outside on these nights, or to peek out of their windows in hopes to catch a glimpse of the supernatural are either killed by the monsters, or spirited away by the monsters. Stay a while and listen. The stories that they have to tell will certainly pique your interest, human.