When the Childlike Empress reaches the home of the Old Man of Wandering Mountain, she has to climb a ladder made out of letters, his message to her.
Her wide white gown was in tatters, for it had caught on every bend and crossbar of the message-ladder. Oh well, she had known all along that letters were hostile to her. She felt the same way about them.
Why is there hostility between her and letters? Especially given that her realm exists only in books which are made out of letters. I doubt this is just a throwaway phrase with no particular significance, given the nature of this story and all its meta levels, but whatever the significance is, I'm missing it.