Grimoire no Shisho: Majin no Miko to Ubawareshi Danpen  

Librarian of Grimoire, Madousho no Shisho, 魔導書〈グリモワール〉の司書 魔人の魅女と奪われし断片

In Grand Esteca's realm, magic exists. The town of Altrium holds a library dedicated solely to sorcery books. Beneath this library lies Grimoire, a potent book of enchantment that once imprisoned a malevolent demon who waged war long ago. Although now diminished and lacking honor, the demon remains an invaluable source of magical knowledge due to his immense power. Mihai, the librarian, cherishes reading books and befriends Grimoire despite his current state. He respects the demon's wisdom even though he is currently devoid of dignity. One day, someone stole pages from Grimoire containing vital magical information. These stolen pages were scattered across different continents. The fear that this could spark a new global conflict compelled Maynard, the sage, to task Mihai with recovering these lost pages.