The Equation of Him and His Little Sister

A brother is caught in a web of obsessive love woven by his younger sister. She believes it is her duty to keep him pure and free from the influence of any other woman, especially his girlfriend. Her devotion knows no bounds, and she will stop at nothing to maintain her control over him.

To achieve her goal, the sister resorts to extreme measures. She drugs her brother, taking advantage of his vulnerable state to satisfy her own desires. As she manipulates the situation, the boundaries between sibling affection and forbidden passion blur, leading to a dark and twisted relationship.