After another round of dual cultivation with six beautiful women, his cultivation level not only reached the eighth layer of the Tianyuan realm, close to its peak, but the purity of his vital energy also increased significantly, reaching thirty-four times that of an ordinary martial artist.
He noticed that thirty times seemed to be a critical threshold—before this level, progress was relatively easy, but after it, progress became much slower.
Moreover, cultivating with Yan's mother, aunt, and both sisters no longer had much impact on improving the purity of his vital energy; only when cultivating with his cousin and sister did he see substantial improvements.
However, although progress became extremely difficult after reaching thirty times, each small increase brought even more powerful results.
