Aika grew up with wealthy parents without any inconvenience. At her parents' suggestion, she married a man far away and lived an ordinary life. One day, she was taught papa katsu by her classmates at school and met a man who took a slight interest in her. While she felt guilty, her throbbing discomfort was lifted. When she met the man again, the kind man tied Aika up with a rope. At first, it was fun to be stimulated a little, but over time, it became addictive to suck on it.