I love the characters! Very sweet.
also SPOILER ALERT
I think.. The way I interpret the true ending is.. They're in an aquarium. That's why the Princess die when she made a crack and there were screams when it happened. the screams came from people. I don't believe that the ocean is that small and the did mention of human and land. Perhaps their ancestors were caught by humans to be put in aquarium and made up the legend for the people's sake. The ancestors obviously knew what was going on and that's how they knew of land and human who walked without tails. That is sad. Love the romantic endings tho