The sisters’ father was a rope artist and their mother a bondage model who toured Japan with their S&M show. These are the family circumstances that they grew up in. When she was young, elder sister Hana was tied up by their father and had sex with him. Younger sister Aya always looked at this from afar with admiration. The suicide of their mother and separation from their father led them in completely opposite directions. Unlike her elder sister, who looks after their father’s studio and has nothing more to do with bondage, Aya became obsessed with ropes. She introduces her fiancé Satoshi, who she met at an S&M bar, to her sister. However, the next day, Satoshi mysteriously disappears... The self-sacrificing elder sister and the free-spirited younger sister. They mix like oil and water, but they will become bound tightly by bonds of rope.