Blue Shrine Maiden

The Priestess of Azure is the ancestor of Mei Amanohokosaka and a minor character in the backstory of XBlaze - Code: Embryo. She is the first of the 'Priestesses of Amanohokosaka' and suppressed the Black Beast for several thousand years.

Information
The Priestess of Azure is only mentioned in dialog between Mei, Kuon Gramred Shutleheim and Tōya Kagari. She was born with an innate ability to communicate with the Azure when she came into contact with the Gate of Sheol. During one of her talks to the Azure, the Gate began to open and the Black Beast surfaced out of it. Believing that she may have summoned it, she beckoned the Beast back into the Boundary and sunk in the Gate of Sheol alongside the Beast; she then sealed the Gate from the inside, sacrificing her life to save millions of others.

From then on, her family, the Amanohokosaka's, began to guard the land, Wadatsumi, that the Black Beast emerged from. Each of her descendants protected the area for millennia to come, until they eventually began to forget their duty; this was until the events of XBlaze.