This creature had sensed how Lothur had killed the demon earlier, using his bloodline and one of his affinities, darkness, to absorb that creature's base Natural Laws.
Since it knew that such beings among demon-hunting humans hardly existed, this dinosaur already imagined that the Seraphim Church would see Lothur as an enemy.
This organization had a monopoly on the human method of slaying demons, so Lothur having this ability without at least swearing allegiance to them would already be a problem. But while the weaker ones in that institution had no way to perceive the difference between Lothur's body and soul, he could easily end up attracting the attention of someone capable of that.
If this happened, this tyrannosaurus rex was sure that the Church would make an enemy of Lothur and kill him, even though this young man's case was not so simple.
Not everyone was willing to take risks like this beast in such a chaotic world.