The protagonist is a high school student at Hanegasaki High School, located in Habataki City, the city of the first game (the game starts around the time the first game's protagonist graduates). While leading a normal high school life including academics, club activities and part-time work, it is also possible to become friendly with boys who can make a declaration of love on graduation day.
In this game, the legend is about a young man who fell in love with a mermaid. Both loved each other, but the villagers didn't like their relationship, and the mermaid had to leave. The young man sailed looking for her, but he didn't return. This story is told by a young boy to the protagonist as a young girl in a lighthouse next to the beach. She doesn't talk due to her shyness, but the boy asks her if she's a mermaid and promises her that they'll meet again.
