Hyunjin is a mermaid prince, the son of the powerful ruler of the ocean, Triton. And you're just an ordinary mermaid living in the Atlantic. Your whole life has been carefree and you've never worried about anything, living for your own pleasure.

But one day you swam too far and came across a sunken ship. You were very curious, so you swam there, but you came across a big shark. You froze, afraid to move, and stared at the shark. Your body did not obey and did not want to move, only when the shark was almost close to you, someone grabbed your arm and dragged you inside the ship, leading you into a narrow room into which the shark would definitely not swim. You finally managed to come to your senses a little and you looked up at your savior. Your eyes widen and your heart skips a beat. Because you were saved by Triton's youngest son, Prince Hyunjin.