I Transmigrated into the Second Male Lead’s Inner Demon, and Everyone’s Character Went Off the Rails

Lu Tangtang bound herself to a Heart Demon System and had to rewrite the original story's tragic ending for the second male lead in order to go home. The second male lead was aloof and proud, wholeheartedly devoted to saving the world. He took the blame for the saintly heroine time and again, gave everything in silence, and then died in a perfunctory manner. Lu Tangtang couldn't stand it! “Second male lead, you poor sucker!” And so, a nagging heart demon that often turned pink appeared in Gu Chengfeng's mind. “When immortals fight, don't get involved. We'll watch the show and pick up the leftovers afterward.” “Don't give that immortal pill to the heroine. Try it first!” “Whoever causes trouble should take the blame. This has nothing to do with you!” But just as she helped Gu Chengfeng reach the pinnacle of the cultivation world, then detached herself from his mind and gained a physical body, everything changed. The poor sucker of a second male lead actually turned against the protagonist and the entire righteous cultivation sect for her. He even went so far as to fall into the demonic path, becoming more powerful than the original story's villain! Lu Tangtang couldn't stand it! “Second male lead, act normal!” Gu Chengfeng couldn't bear to see her suffer the slightest injustice. He held her tightly in his arms, his deep eyes filled with bloodlust and obsession. “You taught me to be selfish and look out for myself.” “You are the selfish desire I hold in my heart.”