*Who am I?* One day, a troubled girl named Kei wanders into an art museum and encounters a painting. The gently swaying water depicted in the painting tells Kei the story of a mermaid. That day, the mermaid fell in love. When she turned 15 and discovered the world above the sea, she sacrificed her voice and her legs to escape the ocean. What the mermaid and Kei really wanted was…