After her father's company went bankrupt, Koharu tried to stay strong and keep going. But the job introduced to her by senior Yumi was beyond anything she could have imagined. It started with just a single contract, yet its power over her was immense and irreversible. The moment Koharu signed that agreement, there was no turning back. Day after day, she was forced to surrender her body, one after another, until she was completely trapped in its web. This story depicts her downward spiral into total degradation.