Ascendance of a Bookworm (Light Novel)
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Novel by Miya Kazuki, You Shiina | A young woman who loves books dies and is reborn in another world as Myne, a sickly child from a poor family. Worst of all, there are almost no books in this world! So Myne decides that she'll just have to make her own and become a librarian.

Rozemyne, Ferdinand, and their Dunkelfelger allies set out to subjugate the Adalgisa villa. But when Gervasio’s absence and a betrayal within the Sovereign Knight’s Order come to light, the party must switch its focus to the Royal Academy’s library.