Eris Violet is the kingdom's strongest hero, renowned for her sword skills and unwavering dedication to exterminating demons. However, after a solo mission goes wrong, she falls prey to the ambitious Minister Kiryuu Tanatsuki. Through psychological manipulation and the use of a potent drug, Kiryuu breaks Eris's spirit and pride, coercing the once-proud heroine into a life of sexual servitude under the guise of national research.