You Promised an Empress, but You Turned Her into a Female Demon?

Su Ye transmigrated into the body of Luo Qinghuan, the female protagonist of the novel he was reading, and bound himself to a “Darkening Investment System.” Under his influence, every time Luo Qinghuan darkens, she receives rewards. These rewards can either be invested or kept aside, but investing in her darkening grants even greater rewards! Thus, Su Ye relentlessly darkened her and continuously invested in her! Time passed without notice. When the crowd of Xuan Tian’s strongest witnessed the young girl emitting waves of dark energy, they exclaimed: “Didn’t you say she had the 先天纯洁圣体 (Innate Pure Saint Body) and would become the savior empress? How… did she turn into a female demon?” *...