Honzuki no Gekokujou: Ferdinand no Yakata ni Te

Ferdinand, High Priest at the Temple of Ehrenfest, had three trusted confidants: knight Eckhart, scholar Justus, and attendant Lasfam. They gathered whenever occasion arose, bringing diverse information to share. What follows reveals their true selves—the stories unfolding behind the scenes of the main narrative.
Reading this will make you love the world of "Honzuki" even more! This is the start of a series of exquisite bibliophile fantasy stories told from the perspectives of the three who swore loyalty to Ferdinand!!
(Source: Corona EX, translated)