That “thing” is bad news.
The shadows told me that there was a hematophage, but that “thing” is high-ranking even for one of them. Not one of the highest, but it’s on another level from an ordinary monster.
It isn’t something a human should ever fight.
He had fought a similar creature only once before. That time, he had just barely managed to defeat it by working with other well-known mages and magecraft-users...but the survival instinct he had built up as a magecraft-user was warning him that the “thing” in front of him was more dangerous than the one he had brought down.

Fate/Strange Fake: Volume 5, Interlude ("Mercenary, Assassin, Vampire I")