Though not related by blood, the stepbrother always treated his stepsister Yui kindly. One day, their father went on a company trip. As soon as they were alone after seeing him off, the stepbrother changed. The stepbrother's twisted affection was directed towards Yui. Confined to the room and tormented, Yui initially resisted but was raped and brainwashed by her sadistic brother, ultimately falling into a perverted love…
