I want to become your partner, Karina Onee-sama... Ruru, a junior student, enters the Punishment Club driven by her desire to earn the approval of Karina, the admired senior girl all students look up to. From slaps and clothespin torture to full-body suspension bondage, toy training, humiliating lessons, pet dog training, deepthroat with a strapon, and forced urine drinking, the harsh punishments inflicted by Onee-sama gradually lead Ruru's body toward pleasure, corrupting her mind and body completely. This work features Ruru Aku awakening to masochism, fully experiencing the world of hardcore bondage BDSM lesbian action. With its intense scenes and the evolving dynamic between the two, this title captivates viewers from start to finish.