In the year 20XX, the eruption of Mt. Fuji has triggered a rapid deterioration of public safety in Japan, and Tokyo has become a city of crime with 1.36 million crimes a year. Chitose (15 years old) transfers from Hokkaido to a high school in Tokyo and meets Ema (15 years old), a classmate whose hobby is watching porn. The girls go out into the dangerous city after school. However, there is a rumor that "Enma," who "disposes" of bad guys in this crime city of Tokyo, exists...?