It is a very large library with six rows of books, with each row having an additional four rows of books. It is most likely owned by Dream Gary.
Role in the episode
In the episode, Dream SpongeBob lands into Dream Gary's Library, and Dream Gary is surprised to see him. Whilst walking around the library, Dream Gary tells him how a dream is like a "window to another realm." He uses an Emily Dickinson book to back that sentence up. Due to SpongeBob's incognizant, He reads a limerick about a man from Peru to him before leaving his library.