I Transmigrated into the Male Lead’s Villainous Master

I transmigrated into the villainous master of the male lead. Just how villainous was he? Si Huachuan took Ji Xingzhi in for one simple reason: to use him as a cultivation furnace. He had pure spiritual roots and extraordinary talent, a natural-born cultivator. If Si Huachuan took him as a disciple, kept him close, taught him well, and made him work hard at cultivating, he would surely grow into a top-grade cultivation furnace. But then...