CAGE

Overview

When two sisters both start a job at a quiet high school, little did they know they were stepping out of the ordinary and into the perverse. It seems that the school they were assigned to is ran by a cabal of perverted teachers and students, who have every intention of keeping the status quo of orgies, public nudity, and sexual slavery at their school alive -- and they're eying the two pretty new teachers who just showed up as recruits, whether they want to join in or not!

Source: AniList