As indicated by the word Gishiki (Ritual/Ceremony) and Jashin (Evil God/Wicked Deity), the central plot revolves around dark cult practices, sacrificial ceremonies, and the summoning of otherworldly, malevolent forces.
The character designs explicitly contrast the mature, developed physique of the mother with the younger, yet similarly voluptuous features of the daughter. This juxtaposition is designed to appeal to consumers of "oyako" (parent-child) themed adult media.
The series revolves around the concept of demon summoning and the consequences that come with it. In a world where the lines between reality and the supernatural are thin, humans have learned to summon and bind demons for various purposes, ranging from gaining immense power to fulfilling desires. The story likely follows characters who delve into this forbidden practice, facing not only external threats but also internal demons.
: Originally a video game (2020), followed by an anime series (2021).