Ending

Satoko was alive the entire time. There was a huge miscommunication issue which made Shinpei believed she passed away. He went on his lonely travels for many years thinking of her while she still wrote many letters for him which return back to her. Anyways, they are both very old and still love one another. In my opinion, I'm disappointed they never got to be together throughout their youth and middle age. So, if there will be a side story, I hope the author will make it awesome to makeup for the setup of Satoko's suppose death and Shinpei's broken heart. They deserve to be together forever.