It sounds like that some sort of fantasy element is involved but it is absolutely not. The movie does not give an explanation at all, other than to compare it to people forgetting their classmates a long time ago. This major point is not reached until one third of the movie. Nothing special happens until we reach two thirds of the movie. I like the climax since it makes full use of the being-forgotten characteristic. I don’t like movies that have no resolution at the end though. The whole thing seems contrived to serve a tear jerking moment, so I’m not impressed. A subplot involving the girl’s father is also incomplete. Excellent film and it is incredibly good. Love the cast and the directing.