Ever since his wife went on a trip with her friends, Hiroshi has been enjoying living alone for the first time in a long time. Then his wife's sister, Haruna, comes to visit... She's so close to him, and Hiroshi's heart pounds as she shows him her alluring cleavage and panties. He tries to escape by getting into the bath, but Haruna barges in, saying, "I'll wash your back." Then she presses her ample breasts against his back...