In 2045, singing is outlawed, and people no longer make or perform music themselves. The MiucS app generates every song for them. High school student Seria Aiba is out with her friends when she hears a human voice singing, something that should be impossible. Tracing it, she finds a ghost, but not an ordinary one: a Great Ghost that has arrived from outside her world. Seria must choose between keeping quiet and putting everything on the line to return music to the world. Her path soon tangles her up with more Great Ghosts, a psychic organization called TERA, and a strange song known as the Possession Requiem, pulling her into a concealed side of a society that has wiped out human music. The series mixes action, music and the supernatural across 12 episodes.