This is a sad story, with a sad beginning and, unsurprisingly, a foreseeable sad ending. I sort of liked the plot, but I am rather indecisive regarding the acting. The story is just a miracle which happened due to love. So far so good. It becomes clear from the onset that this miracle has an expiration date and that it is all about coping with sadden loss. The idea is rather genuine (although it bares similarities for instance with "Ghost", staring Woopi Goldberg and Patrick Swayze), but the realization is quite stylized in a typical Japanese manga fashion. Unfortunately, the developing of the characters (mainly of the one left behind) is unsatisfying - after 8 episodes the mourning lover has not come to terms with what happened, in fact he has not really progressed at all. If the story had some comic instances in-between, I might had forgiven this, but alas this is not the case. So we are left with an unresolved emotional burden (no catharsis, no absolution, no new hope). Perhaps, if the penultimate scene replaced the last one, we would at least have been left with a shimmer of hope.
Generally, the story feeds on the emotional distress induced by the sadness of the event (but not the ensuing plot), offers a predetermined unavoidable course of events. It generally falls under the definition of a kitsch movie/series, namely one that gives no food for thought and just evokes tears through pre-chewed emotions (very much like your typical tele-novella, simply in a more artistic Japanese style).