``I never expected that I, who used to be an ordinary housewife, would grow up and have a relationship like this with my younger brother...'' Aya Kurahashi (Ai Kano), an older sister in her late 30s with two children, is working hard to make ends meet. - He is contracted to take care of the housework for Takumi, the younger brother of a single aristocrat. - However, before he knew it, Takumi had discovered his fetish for mature women and had a secret desire for Aya... - Takumi, who had gotten into a relationship with her after getting drunk, continued to pursue her and proposed a relationship with her. - Even though she says it's for the sake of the family's finances, Aya's body drowns in guilty pleasure as she experiences the pleasure of an affair for the first time...