Where the Sea Meets the Sky (слэш)

Steve is recuperating in a seaside town when he meets a merman. Or rather, a merman finds him and asks — demands, really — to be taken home with him to learn about the human world. And that isn’t even the strangest part...
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“I don’t know what the whole immortal soul and seafoam bits were about. Why would we turn into seafoam? It shows a real lack of understanding about biology, science and magic.”