Head nurse Hisae Yabe, desperate for her son's acceptance into medical school, makes the hospital director promise to help—but at the cost of her body. For love of her son, she surrenders herself, forced to perform blowjobs during work hours and raped against her will beside patient rooms, muffling her moans in humiliation. When a mysterious letter severs her ties with the director, Hisae, overwhelmed with longing, falls into daily masturbation. Then the director's son appears before her, driving her further into depravity as she descends into a lustful, insatiable woman.