During a dangerous mission to save their friend Yuki, Angel and Demon siblings Maria and Ange are captured and subjected to relentless, pleasurable torment by their captors. Forced into servitude, they endure escalating bondage and mutual stimulation, their moans and helpless contractions growing more intense with each session. Their shared suffering and pleasure deepen their bond as they surrender to the carnal training designed to erode their will, awakening forbidden desires.