義父に手篭めにされた未亡人が緊縛調教、乳首責め、蝋燭などの被虐に貶められ、次第に被虐の向こう側にある桃源郷で悦楽に沈む

Chisato, a widow who lost her beloved husband, returns to her father-in-law, but is insulted by her father-in-law in front of the grave. He was a father-in-law who took Senri as his own, cluttering words, but there was love even though it was distorted. What is the fate of waiting for Chisato at the end of repeated training?