When Kadokura Rei found out that her older sister was cheating on her husband, she tried to persuade her to end the affair. But Ichijou Miori, the obedient older sister who always listens to her little sister Rei, did not want to listen to her this time. Even though Rei was angry about it, when she saw that her older sister, who continued with the affair, was becoming brighter and sexier as the days went by, an interest in adultery began to grow in the back of her head. Rei was the CEO of a start-up company, she had no time to think about silly things like adultery, her position was completely different from that of her older sister, who was a simple part-time worker. Despite this, Rei couldn't stop her interest in adultery from growing more and more as she saw how her older sister was changing so much. When she could no longer suppress the intense interest that was growing inside her, Rei decided to... [Translated from the official website]