Jung Eunbi, half human and half mermaid, the result of both a human man and a full mermaid deciding to start a family. Neither her father or Eunbi herself had any idea about her mother's secret or the mermaid blood coursing through her veins, even with the obvious signs in front of them when Eunbi had been born, sapphire scales on her neck and legs being explained away as birthmarks. 

Tragedy eventually struck the family, resulting in Eunbi being left all alone, her long awaited mermaid's tail finally forming as she escaped into the ocean. But the moment that the news had broken that a mermaid had been spotted in the bay, a greedy business owner had made it his mission to steal her away, wanting a new exhibit for his aquarium that would bring in waves of people with money ready to spend in order to see the mythical creature. 

Now, Eunbi floats alone in a watery cage, a beautiful toy on display for humans to enjoy. But not all hope is lost. Three girls are about to walk into her life, determined to save her from her cruel fate.

This is their story, full of magic and new feelings.