Ruriko's father is a well known scientist who's involved in secret research that even his family doesn't know about. Ever since he moved up to the research laboratory in Hokkaido, Ruriko hasn't heard from him. The only thing that reminder her of his warmth was the green music box that he'd left behind for her. She longed to reunited with her father. The little box played music that lifted her spirits, to a place where everything was perfect.