Eiro and Nelly reached the tower of books once again. In here, the spirit monarchs wouldn't be able to bother them. While it was indeed possible to break through the walls if enough power was accumulated, that was not a power that either the naiad king or queen possessed. And of course, once they entered the tower, they had to properly follow the rules in order to proceed; they would have to pass the tests.
Being spirits, they might actually be able to pass the test for the first floor rather easily; the process of analyzing those 'compressed words' was tough, but for beings that were made of magic, it might be easier than for others. Especially for those at their level. But after that, they still had to read all the books of the first floor, then the second, third, and all the rest, to catch up to Eiro and Nelly. And even then, Eiro and Nelly could hide out on the secret floor that was only accessible to Morgan la Fey.
