I'll describe the animation "Mermaid" with 6 literal viewpoints.
Setting: The imagined country where people are banned to imagine something.
Conflict: There was a confrict between a boy who imaged a mermaid and the government which tried to vanish the imagination of the boy. That can be seen as confrict of liverty of imagination and the society's regulation of imagination.
Climax: After a long brainwashing of the government, the boy had to take a fish that he imagined as mermaid back to the sea. After taking back, suddenly, the fish was seen as the real mermade by many people. That can be seen that boy's imagination was win against the regulation of government.
Symbol: The mermaid can be said as the symbol of people's imagination.
Irony: What is the irony thing is that the boy has beautiful imagination power that the fish can be seen as the beautiful mermaid, but around people can see it as just a fish and recognize the boy as kind of insanity because of regulation of the government.
Theme: People should keep imagintion and shouldn`t be banned.