Naoki is a shy boy from the lower class who is bullied by the girls in his class. Furthermore, he is the owner of a bully's perverted, erect cock. However, a savior appears to him! Rima, a transfer student from Kansai with a strong sense of justice, has been doing special training after school to save Naoki and his perverted cock! "Do you want to see those girls again? I'll teach you how to use Ji Po!" From "Do your best with Akan!" And continue to clean up! Even then, Naoki, who gradually succeeds in raising Ji-Po's lower part, makes Lima grow up together with her growing Ji-Po! Please enjoy the story of the bully's upside-down Ji-Po training school!