Gu Yue Fang Yuan was the greatest sword cultivator in China five hundred years ago and a close friend of the head of the Taixu Sect. He fell into demonic ways while comprehending the Sword Path of Supreme Detachment, and died, his body and soul destroyed.
Five hundred years later, Fang Yuan's soul was reborn, sustained by the Fenghuang Down. By chance, Kiana obtained the Fenghuang Down and released Fang Yuan.
But Fang Yuan never expected that a System arriving six hundred years late would bind him to Kiana, making him her guardian spirit.
Wait... an old master from a cultivation novel? Fang Yuan never thought he'd actually become that "old master."
"Kiana, I have an ultimate secret manual here. Want to practice...? Would you like this Fen Jue, or this Great Thunder Sound Breathing Method...?"
"Forget the Herrscher Core and Herrscher powers. Just cultivate Honkai energy directly, and you'll be punching Kevin and kicking the End."
More than any of that, what gave Fang Yuan a headache was that he wasn't the only "resident" in Kiana's consciousness. There was also an exalted queen.
"Mere humans, you think this is enough to challenge the realm of the gods? How laughable."