In a world plagued by the “succubus disease”, a condition where repressed sexual desire causes people to lose their minds, attack others, and transform into monsters—an organization called the “Exorsisters” has been established to combat this threat. A young priestess named Aria is chosen to become an exorsister and is granted sacred powers through a ritual performed by a great priest. As an exorsister, Aria’s duty is to provide sexual relief to infected individuals to cure them of the disease, viewing it as a sacred responsibility.