It is a very sad story.
To those who read this and don't know, Hachiko is the story of an akita rescued from his own's train station. The man pick Hachi up and left for home where his wife await. His wife agreed to keeping the puppy after a few days. Hachi grew a strong bond with the man who saved him. Hachi could not bear him to leave. So, Hachi set out to find his owner one day when he went to work. He would wait for his owner at the end of the day and the man would then take him home.
But one day, Hachiko's owner died of a heart-attack at the school he worked at (he was a professer). Hachi just sat there at the station, waiting for his owner who would never come home again. By dark, some grounds-keepers shooed him off to home. But the next day, Hachi went back to the station to wait for his owner again.
Everyday, for the rest of his life, Hachiko waited at the train station for his own until, he too, evently died on the train station's floor.
P.S. Hachico isn't right, it's Hachiko