Female Prisoner 407: Revenge Sworn In Prison Ichika Hoshimiya

Nami had been helping out at her father's small factory and missed her chance to marry, becoming a woman in her late twenties. She became engaged after a confession from Shimajima, a banker from a client company. However, on the night before the wedding, Nami was attacked by a factory worker and stabbed the man. She was sentenced to prison for excessive self-defense. ...But it was all Shimajima's scheme. Shimajima's goal was to steal the patent held by Nami's father. Sold as a sex slave to the prison, Nami endured countless abuses and gradually became a cold, emotionless woman.