Humming Life(ハミングライフ)

There are many different kinds of lives in this world. When everyone is gone only the afterimage remains.Ai has only recently came to Tokyo. In this unfamiliar city she is a little bit upset. One day lead by a mysterious stray dog she finds a letter inside a hole in the tree trunk. Tomohiro who works night hours at a nursery hadleft it there. Ai being encouraged by this letter writes a letter back and leaves it in the hole. This was the beginning of their strange correspondence.