One day, Manaka is suddenly kidnapped and faces a fate of being sold into slavery. Saebo, a veteran trainer from a hostage trafficking organization, strictly trains Manaka, while the new trainer Minami follows suit, imposing harsh punishments on her. However, due to Manaka's low mental maturity, the discipline only results in inflicting pain. Watching in dismay, her mother Kaori warns Minami, but rebellious Manaka does not resist the training, treating it as a mere "game" and submitting to repeated sessions. Saebo hopes to see Manaka—possessing rare talent as a sex slave—and the inexperienced Minami both grow through their twisted bond.