Hikon kazoku (2001)

Life had been fairly routine for a Tokyo businessman until one day his wife suddenly announces that she has grown tired of life as a housewife and mother, and leaves him and their young son. Soon afterwards, he loses his job and, at his wits' end and unable to pay the rent, must ask an ex-girlfriend to take him in. The ex, a successful career woman still smarting from a recent break-up, decides this kind of platonic relationship is just the change of pace she needs, and agrees. Unfortunately, he neglects to tell her about his son. Will he be able to track down his wife and convince her to come back? Will his ex's former feelings for him be re-kindled? Or will he have to start a new life as a single father?