I'm about to create a list OF ALL ANIME LIBRARY GIRLS YOU KNOW SO FAR
Please, post her name/anime/vn/whatever and you gonna be recompensed
Nodoka from Negima, definitely.
Serika from Choku! manga works in school library.
The character Jibril in the anime series "No Game No Life" was the owner of a large library. There are various book scenes shown in the anime across more than one episode.