Zesshi Zetsumei is the present holder of the Extra Seat in the Black Scripture, she is a woman with heterochromia, for both her eyes and hair. One side of her hair is silver, while the other half is black. Zesshi hides her ears with her hair. Though she looks like a teenage girl, her appearance has not been changed for a long time.
It seems that Zesshi is bored with everything, as there is no one who can barely stand a chance against her. In spite of that, she was implied to have been a bit hopeful of facing eventual defeat one day by someone stronger than her through combat. In particular, Zesshi wanted it to be that kind of individual who she can potentially mate with if such chances are actually possible regardless of their looks or personality.
At the same time, she hardly even bears no emotion of sadness for the death of someone from the same side. According to the Captain of the Black Scripture, Zesshi's attitude was similar to asking about something unrelated to her. For him, this type of attitude fit right in with the style of Zesshi. As well as usually ignoring an important announcement from the Cardinal Conference like the circumstances of her own group.
Due to the circumstances of her birth, she seems to be ashamed of her elven heritage and would constantly hide her ears. Zesshi didn't like it when others such as the Captain of the Black Scripture looked at her ears. Nevertheless, she is hardly filled with neither curiosity or joy on any specific subject until mentioning a potential candidate of doing battle with. It was the urge to fight is what spurred her to have such blood-lust emotions excitingly.
Zesshi was supposedly born to a woman who was once regarded as the Slane Theocracy's previous trump card and strongest Godkin. Prior to Zesshi's birth, the Cardinals stated that her mother was kidnapped by the Elf King of the Elf Country, who later then raped her. Eventually, her mother was rescued by the Black Scripture, but by that time, she was already pregnant with his child.
Ever since Zesshi's birth and at her own urging to the Cardinals, a war of retribution has been waged against the elves for what their King did to her mother. As a half-elf, the girl didn’t like others to look at her ears for unknown reasons why. It had been hinted from the Cardinals' discussion that they didn’t think it was good idea to snatch Zesshi away from her mother’s side. Among the Cardinals, one of them thought it was a mistake done on their part at some point in the past to have raised her with that sort of personality.
Being the Extra Seat in the Black Scripture, she was given the sole task of guarding the Treasury within the Slane Theocracy. It was wherein which the Six Great Gods' sacred items are supposedly preserved. In other words, her main job was to focus on safely protecting that sanctuary, a place that even held their five holy equipment.
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