The demon from the demon world, commonly known as "Jashin-chan," is suddenly summoned to the human world one day. The one who summoned her is Yurine Hanazono, a college student living in a rundown apartment in Jinbocho. Moreover, Yurine claims that she doesn't know how to send Jashin-chan back to the demon world. Reluctantly, Jashin-chan and Yurine begin to live together. However, since Jashin-chan can return to the demon world if her summoner dies, she starts to think about Yurine...! What will happen to the dangerous cohabitation life between the girl and Jashin-chan?!