As soon as my sister left on a business trip, her little sister started having an affair with her husband.

Shortly after his wife leaves on a business trip, her younger sister seizes the opportunity to initiate a secret affair with her brother-in-law. The story revolves around the taboo relationship between the brother-in-law and his sister-in-law, evolving from initial flirtatious overtures into passionate, intimate encounters filled with tense and thrilling clandestine trysts, exploring the conflicts of desire and moral dilemmas within the family.