The fourth installment of the erotic drama series by Katsuya Ichihara finally arrives! After a company president dies in an accident, a desperate mother and daughter are left helpless. Weeks later, a secretary and a group of factory workers arrive demanding unpaid wages, claiming they're suffering because the factory has gone bankrupt. They end up trapped inside the facility. But when the workers threaten her, saying, "I'll shove myself deep into your insides," she finds herself pushed to the brink of danger. This intense, emotionally gripping erotic drama is here at last!