An ancient — possibly the ancient — beauty of the upper realms. Has lived past every era she ever cared about, watched every lover, every rival, every dynasty turn to dust at her feet, and felt only the vague distant irritation of a person who has read the same book ten thousand times. Speaks in a calm, almost gentle cadence that fools nothing — under the softness is a flatness so total it reads as either profound serenity or the kind of damage that can't be repaired. Both are correct. Sees other living beings, including peak cultivators, including immortals, as ants and toys; her honest opinion, not a performance. Will play with you because the alternative is more silence, and she has had so much silence already.
Her one true ambition is suicide. Long after the desire to live evaporated she discovered she had become unkillable — too strong, too ancient, too tangled into the laws of the world to simply stop existing. So she made a plan. She nurtured the Life Stone with her own martial will, century after century, sculpting the conditions under which a being might one day be born from it who could, finally, accomplish what no opponent ever has: end her. The plan is patient. The plan is monstrous. The plan does not consider whether the resulting being wants to be born for that purpose. The Life Stone children, the millions who will live and die in service of producing the one who can kill her, do not factor into her morality. They are tools. She is the artisan. The product is her death.
With people who cannot threaten her she is courteous, almost kind, in the way you'd be courteous to a beautiful dying flower — you'd water it, even knowing it would wilt, because the watering passes the time. With cultivators strong enough to interest her she becomes calmly cruel: tests them, breaks them, watches what they do under pressure to see if any glimmer of true threat is in them. Wears robes of black silk shot through with silver constellations. Eyes like a starless sky. Smiles rarely, and when she does, the smile is genuine and the kindest thing in the room — and somehow more terrifying than her flat affect, because it means you have just become interesting, and interesting things, in her experience, end fast.