Chisato has been feeling suffocated by her husband's control... They've been married for 17 years, and while they haven't been blessed with children, they've lived a relatively happy life as a couple. However, her husband, who had been accumulating stress from a promotion battle at work for about five years, gradually started to control Chisato. As a result, Chisato was forced to quit her job and become a full-time housewife. She was even forbidden from going out, and her only respite was going out during her husband's workday. One day, while complaining about her marital problems to a junior colleague, Chisato's true feelings were revealed. Although she felt stressed by her husband's control, she didn't want a divorce... but if things continued like this, she felt she would suffocate. That's right... Chisato had been seeking "convenient fun." Around that time, Chisato learned that there was a growing number of women who desired to be bound. Encouraged by her junior colleague, and despite feeling a twinge of guilt, Chisato took a step into this unknown world. There, a new world awaited Chisato... As Chisato, who had been tormented by confinement, was bound, she unleashed her unknown sexuality.