Harumakigohan, the popular Vocaloid artist, has released a new game! It's an RPG with a story of music and heart. The story is about a mysterious music called Spica, which is composed of heartbeats. Spica is looking for music to listen to, and the protagonist, Mikage, goes on a journey in a mysterious world to search for songs that will please her friend. Along the way, she meets many characters and goes through a variety of experiences.

GenEi AP: Empty Heart is the first game in a cross-media trilogy by Harumakigohan. The other two games in the trilogy are Reunion and Meltyland Nightmare.