Tatsuya used his summer vacation to visit his aunt Ria's house. Kind and beautiful Ria had been Tatsuya's admiration since he was young, but now that he had grown up, those feelings had transformed into the kind a man has for a woman. However, his aunt had a husband. Unable to do anything about it, Tatsuya was left with a sense of frustration... Whether she knew about Tatsuya's feelings or not, Ria made an unexpected proposal. "How about we take a bath together like we used to?"
