Chunibyo girl in a cultivation world (with a little conscience, but not much) * blackened loyal puppy boy (his conscience has all been fed to the dogs)
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As a bastard whose father is unknown and whose mother refuses to acknowledge her, A Yu is hated for her dazzling, top-grade single spiritual root. Sure enough, right after she is taken to have her spiritual root tested, someone pushes her into the deadly Starfall Valley.
A Yu firmly believes this is just Heaven's test for the protagonist. There must be peerless techniques or rare treasures waiting for her at the bottom of the cliff. But she waits for seven years, while the fierce winds of Starfall Valley nearly turn her into a walking strip of jerky.
Just before she turns demonic, the damn heavens finally toss down a lifeline: a beautiful, gravely injured young man with a purifying spirit constitution, unconscious and unable to wake.
Using the debt he owes her for saving his life, A Yu pretends to be innocent, pitiful, and weak. She takes everything from the young man, tricking him into giving her both his body and his heart. Once she recovers her cultivation thanks to his purifying spirit constitution, she leaves without a trace.
Three hundred years later, A Yu is the young lord of the Immortal Clan and the betrothed of a Divine Lord.
Yet the grand wedding, watched by the Six Realms, is ruined in the war between the Immortal and Demon Clans. A man wreathed in demonic energy cuts his way out of a mountain of corpses and smiles at her. "Liyue, I'm not dead yet. How can you marry someone else?"
The mortal youth who should have died long ago in Starfall Valley, a stepping stone on A Yu's path to immortality, has now fallen into demonic cultivation and is filled with evil energy. Having crossed mountains of corpses and the divide between immortals and mortals, he has come to drag her into hell with him.
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Theme: The years may pass, but devotion never wavers