There is a "school" that abducts and confines girls to re-educate them as sex slaves. Kyoko, a bad schoolgirl, was caught by a witch and turned into student number 55. Life in the school is hell where repeated torture, ill-treatment, and rape is called "re-education". However, Kyoko has a hidden purpose. She was trained by a secret organization called Onesti and infiltrated the school as a spy. Her mission is to retrieve top secret data from the trafficking organization and release the captive girls. Kyoko works with classmates Yuka, Yuma, and Yui to formulate a detailed escape plan. Finally, the day of their jailbreak has come...

Missing 55

Kyoko was the only one who succeeded in escaping the "school", but an unknown virus was injected into her body that will kill her if left untreated. The only way for her to survive is to go back to the "school" and take their vaccine. Meanwhile, Yuka, Yuma, and Yui, who failed their escape attempt, are undergoing brainwashing in the form of severe torture and electric shocks. On the day of the trafficking auction, Onesti armed troops attack the school. There, Kyoko reunites with her transformed classmate. After the fierce battle, can the girls live and escape from this hell?