What Would Happen?
One might think that this was because the current Ailsa was far more powerful than the previous Elena had been. And, this would make sense. Primordial Yin grew more and more valuable the longer a female cultivator held onto their virginity. In addition, the stronger the female cultivator, the stronger their Primordial Yin would be.
However, Ryu felt that the reason was deeper than this.
Back then, he couldn't perceive qi at all. He didn't even understand what it meant to cultivate, so how could he have? With a False Spiritual Foundation, he innately had no affinity to the qi around him.
In that case, it was no wonder he hardly grasped the importance of Elena's Primordial Yin. In fact, until this point, he had still thought that Primordial Yin was some superficial thing too difficult to grasp, believing the true importance in taking a woman's first time was in the melding of his soul with hers.