Where Yuuri is the heir to the throne in the ocean and everyone wants to protect him from the big bad humans because humans and merpeople have a really bad history together.
Yuuri finds a sunken statue of Prince Victor and Loses His Shit. The nose of the statue is broken and barnacles have already started growing everywhere but Yuuri is in love anyway. He’s never seen someone so beautiful in his entire life.
Yuuri bribes all the other mermaids/men for anything related to Prince Viktor and ends up owning an entire cave dedicated to him full of stuff like sunken paintings, robes, jewelry, etc.
Yuuri needs to find a bride to marry and his parents set him up with a bunch of beautiful dates but he’s just not interested. After the dates, he ends up swimming back to his Victor Cave and kind of just floating there and admiring Victor’s face.
At this point, his parents know that Yuuri isn’t straight and decide to give him the ability to turn his tail into legs whenever he wants to so he can go find his love. They kept this ability from Yuuri because they just really don’t trust humans and want to protect Yuuri from them.
So eventually Yuuri and Victor meet on the beach and Yuuri’s fucking naked. Victor immediately starts crying out of joy because he can’t believe the beautiful merman prince he’s watched for every single day since he was a teen is standing in front of him.
Victor then leads Yuuri around all ten of his castles and shows Yuuri his the “Super Cute Water Prince I’ll Never Have A Chance With” shrine in each one.
Yuuri ends up teaching Victor how to swim because humans tend to avoid the ocean due to a fear of merpeople. Yuuri then decides to swim back into the ocean and brings up a bunch of Victor’s sunken things and Victor just flatlines.
They end up getting married and Victor orders that seawater canals be built all throughout the city so humans and merpeople can interact and learn to trust each other.