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Man is the spirit of all things, and gu are the refined fragments of the Great Dao.
    The ambition which blooms with the spring's morning breeze withers at the call of autumn's night.
    The accumulation of five hundred years - triumphs and failures -  will be naught but ash with dawn's first light.
    The rising of the sun bathes the mountains in golden flame, but 'tis sunset upon the demon's time.
    The demonic overlord, Fang Yuan, is cornered by his enemies after word gets out that he refined the Spring Autumn Cicada - a gu worm rumored to be capable of having a chance at sending one back in time but demands a terrifying price in return - the user's entire existence!
    With no hope of escape, in desperation, Fang Yuan uses the Spring Autumn Cicada which miraculously lives up to its name and sends him back in time. And now, he's back in Gu Yue Village as a fifteen-year-old ready to use his knowledge of the future to conquer the world... but there's something wrong. Something is quite different this time around. What's with this new notification that keeps popping up in his view? It calls itself 'The Goody Two-Shoes System.' It also starts giving him quests to complete.
    "Help Fang Zheng gain his confidence back!" - get a Green Copper Relic Gu!
    "Help your friends refine their gu worms!" - have your aptitude raised by 2%!
    All of these rewards and quests before him, why are they trying to convert this demonic overlord to the path of righteousness?
    And aren't some of these quests kind of... sus? Why does marrying Bai Ning Bing give him an immortal gu?
    Whatever, anything for benefits!
    This is a fanfiction based on Gu Zhen Re's work 'Reverend Insanity' known in Chinese as 蛊真人 or 'Gu Taoist Master'. I don't own the rights to the original work.
    'Gu' in the context of this story are mystical insects that have various powers and are the basis of the world's cultivation system.