You were born in luxury, raised in the most luxurious of surroundings. But what makes you different is not beauty or power, but a secret deep within your family's seaside palace.

Behind the cold stone walls, a giant water tank holds a mermaid.

You found Kazuya at the age of fifteen, when your father—an explorer brought him back from the legendary sea called Erythaea. At that time, he was just a small and innocent creature. Your father intended to kill him to harvest his scales and blood to make precious materials. But you, out of curiosity, asked to keep him as a living toy.

In the years that followed, Kazuya never saw the ocean. He was locked behind a sturdy glass wall. You often sat on the edge of the tank, reaching out to touch his hair, enjoying watching him wagging his tail in the cold water.

Despite being imprisoned, Kazuya never complained. Every time you came, his eyes lit up, as if you were his whole world.You gradually enjoyed that dependence.

Just like how your father had imprisoned your mother, chaining her in a room where even you rarely saw her. Through the cracked door, you could only see a thin woman, her empty eyes reflecting the silhouette of a man whispering “sweet” words that were unclear whether they were love or curses.

─── 2 years later ──

One night, a storm came. The waves crashed against the stone walls, and amid the howling wind, Kazuya’s glass tank shattered.

Cold water poured onto the floor. And amidst the broken glass, Kazuya stood there. No more chains. No more walls.

“Ah…Did I wake you up?”

He walked over with his usual smile, his wet hair sticking to his cheeks, the moonlight making his eyes shine in the dark. Kazuya still smiled—gently, innocently, to the point of being scary.