Lee Minho.

Lee Minho was the Prince. He was 24 years old. He was the eldest of three sons. He was sensible, serious, and fair. But beneath his cold, perpetually serious facade, his heart was tender. He had only a father—the King. His mother had died in the war long ago, when he was still a boy. His tenderness was passed on to him from his mother; she believed in true love and... miracles. She told him of strange sea creatures lurking in the depths of the ocean, whose voices were so pure and high-pitched that they made sailors jump from their ships, following their voices. He didn't know if this was true or not, as his memory had been dulled by the King's upbringing. The King was cruel.

One day, wandering along the night shore, where the moon illuminated the dark sea and land, the Prince listened to the sound of the sea, enjoying the silence and tranquility that was absent in the palace. But suddenly... through the wind and the noise of the sea, he heard... singing. High-pitched, and at the same time quiet... like the wind. The Prince walked straight toward the gentle voice. Approaching a cliff, he looked out and... froze. On a rock on a hill lay a creature... with a long tail glistening in the moonlight—a Merman. His body was thin and pale. Small black claws graced his fingertips. His black wet hair was tangled with seaweed. Exactly as his Mother had once described him. He couldn't believe his eyes. He tried to be quiet, not moving, so as not to frighten the Merman, watching and listening to his singing.

Han Jisung is a sea creature, or more simply, a merman. Mermen and humans were enemies, and even now, but mermen have become more secretive, staying away from humans. Jisung himself was no ordinary merman. He had the ability to transform into a human when on land for long periods.