The mother, having lost her husband, started living with her daughter and son-in-law. The daughter has always been stubborn, leaving both the mother and son-in-law bewildered. One night, while the three were drinking together, the daughter got upset over a trivial matter. The son-in-law drank alone and passed out. When Ruka took care of him, he mistook her for his wife and embraced her, leading to intercourse. Since then, an awkward atmosphere remained between the two. After that, unable to forget the unforgettable memory, Ruka comforts herself alone. One day, her son-in-law accidentally sees Ruka masturbating and can't hold back his feelings, expressing them and embracing her…
