In the past, Lilith did not want Bai Zemin to use this kind of attack. As for the reasons why she preferred to keep him away from such a style of combat even though many things would be easier if he could master it, only Lilith herself knew.
However, she realized that there were things that could not be avoided. Just as Bai Zemin had said yesterday, even if Lilith was one of the most powerful existences in the universe she did not have the ability to fight against fate.
In theory, Bai Zemin should not know of the existence of this attack method until much later. However, due to his title 'Irregular' and the ability to travel between worlds, as well as Princess Seraphina's 'Invocation' skill that probably played a large role in Bai Zemin's appearance in Eventide World, things had taken a 180-degree turn that Lilith did not expect; she did not expect to meet an existence that curiously carried a greatsword and at the same time wielded it using a whip in the hilt.