Rie, who is still unmarried even though she is in her forties, lives alone in her parents' house. Then, Rie's younger sister Sanae and Sanae's daughter Ruka come to visit for the seventh anniversary of their mother's death. For a while, the three women live together under the same roof. Then, one day, while Sanae is out to eat with a friend, Ruka's feelings run wild. "I love mature women like aunties..." Rie is confused by this unexpected turn of events, but her unsatisfied body, which has never been satisfied by anyone, cannot resist...