A virtuous mother, Chisato, who lost her husband and raised her son alone, has devoted herself to supporting his academic ambitions. However, when financial difficulties threaten his admission into a doctoral program, her son's professor becomes involved. Initially sympathetic, this lecherous academic gradually reveals his depraved nature, exploiting the situation to seize control over both mother and son within their own home. Though a scholar of Japanese literature, he harbors twisted sexual desires. As the bond between mother and child is torn apart by manipulation and domination, how will Chisato confront the escalating abuse and incestuous violation?