After losing my mother for three years, my father remarried a charming and attractive woman. And I found myself drawn to her... Just seeing Kozo-san cleaning or imagining our lewd relationship while she's bathing became a daily obsession... Starting from one day, I began to watch over Kozo-san... Sneaking a peek at my father's night life with jealousy, but one day, as usual, while spying on Kozo-san, I saw an unbelievable sight...