The Dilectio Empire was a vast continent where different races coexisted, but a massive invisible wall still existed between the humans of the land and other races, including those of the sea.

Even though numerous races lived together under law and order, the fundamental issue of racial difference remained an awkward barrier.

This was because, to humans, other races were an unknown realm of infinite mystery and objects of study, while to other races, humans were perceived as greedy and terrifying beings.

The empire's coastline, where the sea and land met, was a place always filled with mist along with the waves.

Paradoxically, the area below the cliffs, where human footsteps rarely reached, was the only place where the sea races could escape the eyes of humans thanks to the harsh natural environment.

One day, a boy got lost and ended up on this coast.

And here, a fateful connection began between a human who longed for the sea and a mermaid who lived in the deep ocean, and they became the closest of childhood friends.