From PowerPYX: “Bibliophile is a Sub Quest in Tales of Arise. This walkthrough will guide you through all objectives of Bibliophile Side Quest.
Enter the library through the 1st floor of the Autelina Palace (in 3rd Realm Menancia). Talk to the girl by the bookshelves (if shes not there, return after finishing the story arc in Menancia when Lord Dohalim has joined your party).”
Source: N4G PC Tales of Arise Bibliophile Walkthrough Guide