This was one of my favorite songs as a child. There are multiple theories about the meaning. I think my meaning is different. Here is my take:
A boy grows up and stops playing with Puff.
Puff ceases his fearless roar his head bent in sorrow green scales fell like rain.
Without his life-long friend, Puff could not be brave. The mighty dragon sadly slipped into his cave.
The boy lost his innocence, child hood. He becomes an adult. As we grow older, we often let go of childhood things and life is dragging or dragin’
I think it is sad. I feel for Puff because that is how I am. He loses his one and only friend and now is alone. Puff needed the boy for strength. Without the boy he is no longer fearless and hides away.
This is what it is to be alone. Maybe I am like Puff. I am fearless and brave with others around but alone I hide. My head is bent in sorrow. And I am dragin’.