This card is based after the Hyakki Yakō, a Japanese folk belief. The belief holds that every year yōkai, the Japanese supernatural beings, will take to the streets during summer nights. Anyone who comes across the procession will die, unless protected by some Buddhist sutra. The game Hyakumonogatari Kaidankai was based on the folklore.
This card and the folklore of Hyakki Yakō, has an alternative copy relating to "Factory of 100 Machines", which has a title of 「百機夜工」 which means in Japanese "A Night of 100 Machines" and is also pronounced as "Hyakki Yakō". Both these titles had a major difference in Kanji terms but no difference when heard and often was confused between this card and "Factory of 100 Machines".