Angor considered himself lucky that he finished recording the books a day before Sunders' return. Other than that, nothing special happened.
Angor was still tensed upon seeing Sunders, fearing that his teacher might have some ways to monitor his actions in the book room. His worry was soon proved to be unnecessary. Sunders was not interested in which books he read. The man only told him one thing, "Once we get back to Brute Cavern, keep in mind that you won't receive anything easily."
Angor was unsure about what he meant. Later, Flora explained to him in private, "I was pulling your legs the other day. The books you read that are intended for apprentices aren't valuable to wizards in the least. But still, you need to obey the equivalent exchange rule. The teacher was telling you that if you want to find books to read in Brute Cavern, you must pay with magic crystals."
… So Flora exaggerated the books' value just to scare him.