The name of secret organization next only to the Original XIII that comprised of high-powered battle-type Battle Dress: Dubhe, Merak, Phecda, Megrez, Alioth, Mizar, and Benetnasch. While their outward appearances are Schuster's loyal pieces, each belong to either Leviathan (ocean), Ziz (sky) or Bahamut (land) unit that maintains the public order in the Blue World, in truth they are group of people with the same intention as Administrator Polaris.
However, neither Polaris nor themselves aware of each others. Asterism is said to be created as Schuster's backup.
They are divided by each day of the week and made to back up the incident on that day. Though there are no significance in each one of them, Schuster's security is protected by regular integration of their data. Conversely, it is possible to influence Schuster by rewriting the Schuster data inside them, logically, security is not sweet.
Asterism is a pattern of stars recognized in the Earth's night sky. The name of each member of the group are derived from the stars in the Big Dipper asterism.