Tokyo Family Court judicial research official Akira Yamanobo is in charge of Tetsuo and Ayano Katase's divorce arbitration. Ayano, the wife, who works for a boutique company, insists her husband is involved with another woman. Supported by her employer Kotomi Saegusa, the company president, she demands a divorce as soon as possible. On the other hand, her husband Tetsuo, a trading professional, denies having a relationship with a woman. He says he will not agree to the divorce and does not plan to let his only son Kenta go, so the arbitration continues. According to Akira's investigation, Ayano gave birth to Kenta as a single mother five years ago when she was working as a hospital clerk, making him Tetsuo's stepson. Tetsuo loves Kenta as his own child, so Akira doesn't understand why Ayano is so insistent on getting a divorce. However, Tetsuo's insistence on not giving up custody of his stepson Kenta is also very unusual.