Prison 13

Mari (Mayu Hotta) is a female university student. She takes part in an experiment held by popular VTuber Sophia. When Mari arrives at the place where the experiment is to be held, she notices the place looks like a prison. 12 people participate in the experiment and they are assigned roles of prisoners and prison officers. The experiment takes place over 7 days. Mari is assigned the role of a prison officer. The experiment turns violent.