Brown Notebooks are used to earn illicit pets such as the Streeler and Kneazle. They can also be used to purchase different skins and looks for your other pets. Brown Notebooks can be earned by particpating in events such as House Pride or Collect Stars, or by taking advantage of in game offers.

Here are the pets you can earn with Brown Notebooks:

Crup - 50 Brown Notebooks
Streeler - 50 Brown Notebooks
Kneazle - 60 Brown Notebooks
Puffskein - 80 Brown Notebooks
Spider - 100 Brown Notebooks
Puppy Crup - 120 Brown Notebooks
Kneazle Kitten - 120 Brown Notebooks
Bat - 130 Brown Notebooks
Owlet - 140 Brown Notebooks
Moke - 100 Brown Notebooks
Jackalope - 110 Brown Notebooks