U12 (Series) favorite_border

[DeepL Translation - needs review] Introduction to Volume 1: Twelve girls are trapped in a mysterious prison. A mysterious man appears before them and declares, "Your human rights will be suspended. And suddenly, an event for the prisoners, a "fun party" begins!　The girls begin their struggle to get through this unreasonable and abnormal situation!　A shivering girls' prison escape survival!

(Translator: DeepL)