Rental oneesan: Yokubô kaseifu (2006)

Chinatsu is a "Rental Big Sister"—a super-housekeeper who handles not only daily chores for elderly people without family and men living alone but also their sexual needs. Upon arriving at Sanzo's home, she would take care of the cooking, laundry, and cleaning; while washing Sanzo's back in the bath, she would open her body to him. A year earlier, Chinatsu had been an office worker contemplating a career change after running into trouble with her boss, Yazaki, with whom she was having an affair...