Sato (formerly Chitose) was living a happy life with her beloved husband, Koichi. The devoted husband Koichi bought an apartment in the suburbs and worked hard to repay the loan. For job hunting purposes, his younger brother Nobuo would be living with them for a while. Nobuo had been eyeing Sato's body for some time, and one day he succeeded in having intercourse with her. From that day on, Sato's lust began to bloom. Unaware of their relationship, Koichi continued his life as usual, while the illicit affair persisted…
