Reira gets so angry during an argument with her husband's mistress that he pulls out a knife and ends up injuring her in order to protect herself, resulting in her being sent to prison. Reira, who spends her time as a model prisoner in an effort to shorten her sentence by even one day, is ordered to do special volunteer work. The content of the activity was to use the anus to treat the sexual desires of violent criminals in order to release their stress. Believing that he would be able to return to his normal life if he endured for six months, he continued to receive butt training from the guards and prisoners, but...