Kuon no Mori 

Shiorigahama, a town where only bibliophiles live. High schooler Uozumi Yuushi moves with his parents to Shiorigahama, to his late grandfather's house. Yuushi inherited his grandfather's bookworm status, and has a special skill in that once he reads a book, he never forgets its contents. After changing schools, Yuushi finds his way to the Shiorigahama library and there swallows a letter-eating fish (the silverfish). Then a mysterious girl appears right in front of him and...