​Discover the immensely popular h-series that changed the history of adult animation with its scenes of violence, perversion, and lust. Dive into the world of hardcore sex and unusual sexual fetishes with Isaku, Shisaku, and Kisaku – three anime titles named after the sadistic brothers they revolve around. Follow the journey through episodes filled with explicit content, without games or recap episodes. In this episode, Isaku, experience the hidden secrets of the girls’ dormitory at Shukusei Music Academy. Behind closed doors, talented young musicians showcase their darkest desires, as the school handyman, Shusaku, becomes entangled in a web of blackmail and sexual degradation. Can Shusaku satisfy his insatiable hunger for pleasure while maintaining this secret world? Explore the forbidden pleasures and uncharted territories of adult animation with Isaku.​