When her husband Kazuhiro's older brother Masayuki fails at work and loses everything, he ends up staying with her for a while. His wife Mako is hesitant but accepts her husband's proposal... Although Masayuki has been divorced for a long time, he can't contain his excitement at the thought of another woman living under the same roof, even though he knows that she is his younger brother's wife. Mako, who is troubled by her illicit affair with her brother-in-law, spends her time worrying that Kazuhiro will find out, but whether he knows it or not, Kazuhiro treats Mako as if he always hadn't changed...