Among the Demon King's Four Shining Stars was a fifth that surpassed them in everything - Akaoni Starkfall. He is the boyfriend of Rebecca Bluegarden and Homura Kōgetsu but also the adoptive brother of Hermit Mio and Elsie Crimson.

He once worked as a scientist at Müller's organization but betrays them by saving Hermit and killing them while blowing up their lab. Some years later, he was trapped in a mysterious planet next to Bluegarden Planet.