Nao is suffering from her husband's domestic violence, while Rio is being forced into an unnatural relationship with her father after her husband goes missing. Despite their secrets, they manage to maintain a good relationship as neighbors. One day, Nao is assaulted by a suspicious masked man. Panicked, she consults Rio, who introduces her to a detective to investigate her husband's disappearance. But with her missing husband, a shady janitor, a lecherous father, and a mysterious detective, who are they really targeting? What is the true objective of the <Intruder X> threatening these two big-breasted wives?