The main characters of
this story are a boy who likes to imagine and a fish which turns into a mermaid
by his imagination. He was arrested since the world where he lives in does not
allow people to use their imagination. However, he managed to run away from the
prison and found out that a mermaid was actually the real and his imagination
turned out to be true.
I think that the main theme of this story
is that we should never give up something you believe in just
because people around disagree with you. It is important to
keep believing what you think is true. Also, I suppose the author of
this story wanted to suggest the importance of freedom that everyone is
supposed to be given.