The ninth installment of the "Documentary: Close-Relation Incest" series dares to cross forbidden boundaries. This time, it portrays a dangerous affair between a sister and her brother-in-law, who begin living together at her parents' home after her divorce. Following her divorce, the sister spends her days at home constantly wearing short pants, sometimes even walking around topless. Her brother-in-law can't help but be drawn to her appearance, overwhelmed by uncontrollable desire. Six months after her divorce, with no boyfriend in sight, the sister harbors deep sexual longing. Desperate to deepen their relationship, the brother-in-law aggressively pursues her, leading to intense emotional conflict and a perilous romance that pushes past ethical limits.