The Demon Supreme Kai exist as though in opposition to the Supreme Kai and govern evil, though the Supreme Kai's power is greater at present.
Though they are never directly addressed as "Makaioshin", there are hints that Demigra and Mechikabura may be Demon Supreme Kais ruling the Demon World, thus Makaioshins.
As a Demon God Demigra wears green colored "Potara" earrings, and only Supreme Kai can wear these. In the Dark Demon Realm Mission manga Demigra states that he will become the new Supreme Kai of Time. Originally, several of Demigra's concept designs depict him with Supreme Kai clothes.
In his prime Mechikabura wears green colored "Potara" earrings, and only Supreme Kai can wear these. He also wears Supreme Kai clothing. In Ultimate Mission X it is said Mechikabura tried to become the Supreme Kai of Time.