It is a hardcover book with a red cover that depicts the title transcribed in yellow letters. It is shown to be chewed up and covered with saliva, due to Puffy Fluffy's fight with Gary over the night. Concept-wise, it is a memoir of T.S. Halibut.
Role in episode
Upon waking up to pieces of his roof on the ground of his bedroom, SpongeBob assumes that a seaquake occurred while he was sleeping. He goes downstairs to his library and notices that everything is a mess and that the logs from his fireplace affected the room overnight. He then picks up his prized memoir of T.S. Halibut and sees that it's chewed up and covered with saliva. He suspects that Gary is responsible for this because he is jealous of his new "friend."