While he isn't directly described as being gluttonous in the traditional sense of overeating, his focus on acquiring knowledge and books, often at the expense of practical necessities, can be interpreted as a form of intellectual gluttony.
He is described as being "thin as a rake" and "not fat," but he prioritizes acquiring and studying books over basic needs like food and clothing. This suggests an obsession with learning that might be considered excessive and could be seen as a form of gluttony.