S1, E1: Naoya Aizawa is an exemplary businessman who married his colleague, Kana. He is balancing work and marriage when a new employee, Noa Tachibana, joins his firm's branch. Noa is attractive and quite capable at her job, causing Naoya to acknowledge her. Meanwhile, Kana works at a different branch with her colleague, Minagi. Although they are good at their job, they struggle to train two new employees, Omura and Koyama. One day, Naoya goes to drink with his subordinate, Hirano, and Noa shows up. Hirano is uninhibited, and states that cheating is okay as long as your partner does not find out. Naoya takes marriage seriously and dismisses the idea, saying that cheating is something only idle people do. Hearing this, Noa takes an interest in Naoya and slowly starts to get closer to him.