Transmigrate into a Book: The System Forces Me to Raise the Great Demon God

[Transmigrate into a book + System + raising a child + punishing scumbags + hidden strength]

I woke up to find myself transmigrated into the world of The Journey of Flower as a dying orphan fleeing famine! A cold-blooded System bound itself to me on the spot: [Mission: Raise Hua Qiangu until she turns sixteen. Warning: Do not interfere with the main plot. Violators will be erased!] Looking at the scrawny little girl everyone called the “ill-fated lone star,” and the gravely ill but kind man who took me in, I gritted my teeth and accepted. Can't change the plot? I'll find loopholes! I keep up with the System's missions, secretly feed her spirit rice and immortal pills, and train in peerless techniques behind the scenes. I raised Xiaogu from a sickly, sallow child into an adorable little darling, the luckiest girl in the village and the envy of all. I thought I could quietly protect her as she grew up, until, Bai Zihua, the immortal of Changliu, arrived right on schedule, still as graceful as ever. Xiaogu tugged at my sleeve and said innocently, “Sis, that Daoist is so handsome.” I smiled and ruffled her hair, but alarms rang in my head: Was fate's wheel finally turning? To my surprise, the System's alarm blared the very next second: [Warning! Warning! Hua Qiangu's fated calamity of killing her father has not been triggered! The worldline is beginning to collapse!] I went ice-cold. How could this be? I clearly saw it happen with my own eyes... The power I'd kept hidden suddenly spiraled out of control, and spiritual energy surged around me. Bai Zihua's piercing gaze immediately fixed on me, the “ordinary mortal.” Only then did I realize that I had been the greatest variable all along!