Disregarding the politics of how complicated it'd be for society overall or at least more villagers to accept the mermaids, beautiful romantic story of a
offspring boy (part mermaid in lungs) who like his father fell in love with a mermaid girl when she met him while playing the piano underwater of which the mermaids throughout the years forgot how to play.
The moment of
lethal fear when her instincts bit his ear off when a shark attacked him drawing out blood was interesting to reveal the dark possibility of mermaids in how they could eat humans.
It's sweet in the end but I have a hard time imagining unique or many thrilling plots throughout the story if it became a manga of which it didn't. 7/10.