I don’t doubt that Dracula’s library has a lot of information. But if you need to know about monsters, monsters specifically-

[ He takes Alucard’s hand and brings it to a firesteel on a short chain and a flint set into the wall by a torch. He doesn’t possess the dexterity to light it in a form he’s so unused to, but Alucard does.

If he lights the torch, it illuminates an entire library they’re standing above. ]