After his wife returned to her parents' home, Daisuke's daily life had become lazy and disorganized. Into this routine, his wife's older sister, Chihiro, suddenly arrived to help with housework. Daisuke, who had been frustrated by his messy, cluttered room, welcomed her visit—but gradually became distracted as he caught glimpses of her panties and her alluring thighs during cleaning. Unable to resist, he let out an audible gulp. As Chihiro innocently leaned close with her charming smile, Daisuke's self-control began to fade completely.