What do Edgar Allen Poe's short stories "The Black Cat" and "The Cask of Amontillado" have in common? A. Unreliable narrators
B. Animal imagery
C. Supernatural horror
D. Dark Humor
E. Omniscient narrators

we should all just get dogs.

misty passage from the question

  this riddles' answer is library.

  the "leaves" are a reference to the books' pages that the library contains; the branches are a network of libraries that connect multiple libraries' collections, resources, and items in a system of a common database, integrating them; the branches' organization are a useful management tool for coordinating the multiple collections many libraries have.