I shall attempt to elaborate on the parts that have caused much confusion. From what I can infer, the library of the Gods records all such knowledge from different dimensions in archives. Somehow and mistakenly so, a page from the book of a different dimension was added to the book of the present world thus, leading the previous librarian to step in. Now, I am certain that finding such a page or deciphering how to remove it from this book would entail acquiring quite a few resources. Perhaps in search for such resources, he had to split his power or he had encountered something that necessitated him to do so but regardless, he had been split in two parts, one being him and the other, would be a female counterpart, who would then end up becoming the Saintess and dying with one of the keys after exhausting her powers. Therefore, Yog is the current librarian who has occupied the position of the previous librarian [who is also the current Pontiff in the present world] for whatever reasons and that has prevented the previous librarian from returning to his position as well. He also reveals that the first Saintess was Rosalynn. As for the Pontiff, he had foretold that there could only be one Saintess according to the prophecy, and if we correlate this fabrication with the information that Yog has provided, then certain things do make sense. I hope that this has helped you somewhat, in understanding all that has transpired in this chapter.
Pretty sure hes ml's step bro or smthn
Poison tea?
Nice, you should have said that since
Mangekyo sharingan it is. Even the stealing, copying and countering a spell is kinda the same.