Crookshanks loves the scent of paper. He is very much at home in his witch's library. And he does put a paw on the bag, when Katsuya tips it down for him to inspect. Then nods as if satisfied.

Once they are in the magical district, Crookshanks feels very at home here. He enters the shop with Katsuya, sniffing around again. His whiskers twitch. Then he meows and heads towards a secluded corner of the shop, that seems to hold the elite and rare magical spell items. He can smell a Basilik nearby, so there must be a scale here.