Astres

Astres was one of the four heavenly kings from the demon army. However after failing to bring back the mermaid princess (Plati), had her whole army defeated (by Noria and the rest) and brought a dragon into the battlefield (that's when Veil sent her back and went there), her title was revoked and she was exiled from the demon country. After being kicked out of the demon territory she came back to find Noria and ask him if she could work under him, and he welcomes her and her two subordinates that were following her, Batemy and Belena.