The Uppermoons are a group of the six (technically seven) most powerful demons in the world under Muzan, the demon king’s, control. They are numbered by how powerful they are, one being the strongest and sixth being the weakest. Kokushibo is upper moon one, Douma is upper moon two, Akaza is upper moon three, Gyokko is upper moon five, and Daki and Gyutaro share the spigot of upper moon six since they are siblings.