While Negary was in the Flame world, his temperament was always very aggressive, humans were no different from pieces of bread in his eyes, food to be consumed.
As such, whenever humans looked at him, they would feel the sense of primal fear that originated from their instincts, an extreme sense of discomfort and danger of having each and every cell in their body dominated by another. His existence itself was a provocation to their wits and reason.
But that was because everything was a lot more transparent in that world. The principle of the weak being prey to the strong was a lot more obvious, and having strength also meant having a great sense of charm and charisma. It was for this reason that most people chose to pledge their allegiance to Negary rather than the alternatives.