Toshokan no Daimajutsushi

In a distant world reminiscent of Arabian Nights, a mysterious young elf-child etched by a difficult life in the slums of a remote village with his elder sister.
One day, he encountered Sedona, a librarian from the greatest library of the land, and the two formed a bond as they began their adventure in a fantastic and wondrous world.

(Source: Mangadex)