When adult magazines are banned within a prison, a complaint is filed, accusing the authorities of human rights violations. A high-ranking government official steps in to resolve the issue by reinstating the previously suspended pen pal service. While carrying out her boring correctional work, a female prison guard, assigned to monitor the correspondence by censoring letters from prisoners, comes across a pen pal letter with explicit contents, which sparks her unusual fantasies about male prisoners. She eventually becomes overwhelmed by the strange emotions and secretly sneaks into a male cell block filled with dangerous criminals.