A pirate's siren

Just a tiny Pirate×Merfolk AU one-shot with Law and my OC Nero that might escalate into something bigger too, just like the One Piece fantasy AU I'm 😂💔

Generally, it will be settled in the Great Era of Pirates. Law, who's also the crew's doctor, sails across the seas along with his mates, stealing, drinking, killing, trying not to get caught by the Navy, surviving - leading an ordinary pirate's life. Nero lives the life of any other of the sirens and merfolks in the deep seas, exploring the ocean and showing interest in humans. A chain of unexpected events leads to a meeting and clash of both worlds.

When the folk of the seas gets dry enough to not be covered by the thinnest layer of water anymore, their tails split into legs so they could be able to roam and live on land like humans.

Humanity's world is reigned by the World Government in most parts and the seas are controlled by the Navy. The inhabitants of the seas live under the rule of two heads - the regular ruling head King Neptune and the Emperor Whitebeard leading a large group of mer- and fishmen into battle, protecting the realm under sea level from most harm.