This is one of my BFA final assignment in 2011 which is based on the book "Jennie"(The Abandoned) by Paul Gallico.
In the story, Peter, a British boy turned into a cat, is trying to survive on London street. A stray tabby named Jennie became Peter's mentor, and they had an interesting adventure in 1949.
This sequence is the very end of the book after Peter becoming back to a human boy, and the memory as a cat slowly fades out.
You can also see this animatic on Vimeo.