Six years ago, Leon, an ordinary male merfolk, had an unexpected encounter with the Merfolk King, Areno, and later gave birth to Finn. Six years later, Areno learns that he has a child and begins searching for him. To pay for Finn's healing, Leon applies to become an attendant at the royal palace, where he reunites with Areno. Areno immediately recognizes Leon as his destined mate and pursues him relentlessly. But the noblewoman Lilith, driven by jealousy, repeatedly targets Leon and Finn. As the truth comes to light, Leon is revealed to be the long-lost son of a noble family. In the end, the villains face justice, Leon and Finn are reunited with their families, and they begin a happy life with Areno.
