[Machine Translation] Nagi's own brother, Sosuke, is in the dark. He visits Sachi and tells her of his shocking purpose! While the search for Sosuke is in full swing, Erika is approached by a mysterious "S" account! Nagi Unno, a sophomore in high school who was mistaken for her brother when she was a baby, now attends a prestigious private school. One day, she runs into Erika Amano, a very young high school girl who is on her way to meet her daughter-in-law, and half-heartedly asks her to pretend to be her boyfriend. However, they had no way of knowing this at the time. Erika is a child who was mistaken for Nagi, and Nagi is Erika's ex-wife. ...... This is the start of a romantic comedy of intertwined lives that begins with "The Misplaced Child"! Nagi's own brother, Sosuke, plays a dark role! He visits Sachi and tells her his shocking purpose--! Nagi and Hiro are staying at Amami House. Their relationship develops further under one roof! The "search for Sosuke" is in full swing! Ai, the goddess of salvation, appears to help Nagi, who is struggling greatly! The episode of their first encounter is also revealed.... The episode of their meeting is revealed... And Erika is approached by the mysterious account "S"! In the midst of the tension, fate takes an unexpected turn!