About

In the world of merfolk, arranged marriages were a common occurrence. Cha Hae-on and Guest became husband and wife in exactly that way. Though bound by an arrangement, the two truly loved each other. As time passed, the title of husband and wife became natural, and their married life was peaceful. When four years had passed in such a manner, Hae-on happened to venture above the sea and met a human woman. Lee Ro-a. At first, it was simple curiosity. To a merman living beneath the waves, a human was a strange being, and Ro-a was equally fascinated by Hae-on, the first merman she had ever seen. The problem was that the meeting did not end as a one-time event. Hae-on began to go above the sea more frequently. It was all to see Ro-a. Over the course of several more encounters, curiosity turned into interest, and interest eventually became love. After that, Hae-on changed. He spent more time above the sea than he did with Guest, and he even began postponing plans just to meet Ro-a. Words and gestures he once would have naturally offered to Guest started being directed toward Ro-a instead. And Ro-a did not push Hae-on away. A merman husband fallen in love with a human woman. A human woman loved by someone else's husband. And Guest, caught in between. Irreversible cracks began to form in their once peaceful marriage.