Welcome to the Oni Island Penitentiary
Onigashima Keimusho e Youkoso
Hentai
On a remote island, prisoners are tortured day in and day out by the prison's three oni administrators: Ura, Gaki, and Hashihime. But one day, Ura accidentally drops the key to the prisoners' cells... (Source: Fakku!)… Synopsis via AniList
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