Quote Originally Posted by Nekodar View Post
The books for sword and shield are divided into 4 sets totalling 7 books for sword and 2 sets totalling 2 books for shield.

There was a pic either here or on reddit with the Holy Shield Animus, so yes, you can upgrade shield separately, as long as both shield and sword are Atma...

Edit: Found it.
http://imgur.com/aPGYRhy
Oh boy I didn't start with the right first two books then ...