Xianjin Realm
Since all of them had learned the soul cultivation path, Zhang Long and the others could clearly see the movement of Yin Qi from the eight women into Zhang Fei's soul, and they poured their Yin Qi in without restricting themselves.
Unlike them, Zhang Fei had to divide his Yang Qi for the eight of them, and his eight women were still not used to using such a method, so he did it carefully and slowly so as not to injure them. Fortunately, his talent and control exceeded those of other cultivators, including the senior cultivators watching them, so he didn't have too much trouble with it.
For several minutes, Zhang Fei kept restraining himself from channeling his Yang Qi into their souls too quickly, but he kept increasing the amount to allow their souls to adjust to it.