Disintegrating Thesis Note
Looted off monsters in Bedlam.
These are the keys to enter the lair of the resident Peerless, the Monstrous Interred Grizzle. You need to collect 5 of them and exchange for the Librarian's Key via Master Cohenn's quest, called "Misplaced." The reward for that quest, the Librarian's Key, is what's used to enter the Peerless Room.