This document is the personal bestiary of a unnamed hexenjager, one of those unfortunate souls whose life is overtaken by the hunt for witches. As such, their account focuses on the various kind of hags and witch-work they encountered, but in their travels they must have fought other agents of darkness as there are entries here detailing monsters unconnected to the foul rites of witchcraft.
From the passages detailed therein, it seems quite possible that this hexenjager patrolled Krevborna's coastal region (perhaps being based out of Piskaro), or at least specialized in the hunting of water-witches. What became of this hexenjager is unknown; may the Saintly Blood preserve them in their holy work or grant them a place of rest in heaven if the worst has come to pass!
(This is a pdf an exercise in reskinning; I took stats from from the 5e Monster Manual and gave each monster a folkloric or Gothic twist to fit the mood of Krevborna. You can download it for free here. Twelve pages, twenty-four monsters.)