Ruri married Ryuichi, her classmate from school days. She discovers that her newly introduced father-in-law, Ken, bears an uncanny resemblance to her beloved father who died of overwork when she was a child. Ryuichi, having inherited his parents' company through connections, struggles desperately to prove himself by working tirelessly. Amid this pressure, Ruri and Ken gradually grow closer. One day, a crisis strikes Ryuichi's company—continuing business with a client requires Ken to return from retirement. Fearing Ken might collapse from overwork again, Ruri takes drastic action and begins seducing him physically. Each step she takes becomes a catalyst, deepening their forbidden relationship.