Grimoire no Shisho

In the magical world of Grand Esteca, the town of Altrium houses a vast library containing every tome of sorcery. Deep beneath it, 30 floors underground, lies a sealed book of immense power: the Grimoire, which once imprisoned a demon who ravaged the world in a great war. Now, that demon has become a lecherous degenerate lacking all dignity. The librarian Mihai, an avid book lover, befriended the demon and respects his profound magical knowledge despite his fallen state. But one day, someone steals pages of knowledge from the Grimoire, scattering them across continents, threatening to spark a new world war. The sage Maynard orders Mihai to retrieve the lost pages. From Hau~ Omochikaeri!