In order to save her people, Mina, who became the High Priest after growing up, made a deal with the demon. She threw fruits tainted with corpse poison into the human world to collect vitality for the demon to increase its power. In return, the demon used its demon aura to change the half-immortal physical characteristic, so her people could live in the human world.
Eventually, when Sophia Jenkins, the protagonist, and her friends came to the Demon Palace to slay the demon, Mina exhausted all her strength to contribute her power to the protagonist's team. They successfully killed the demon, and she, holding her already deceased sister, returned to the collapsing palace. She disappeared within the frozen city.
She assumed all sins for the outside world, claiming it was her own fault for being deluded by the demon and committing grave mistakes. To make amends to the Cultivation Sect in the lower realm, she sacrificed herself along with the city.
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