Malevolence is... [A thoughtful pause before he grins.] It's similar to the nightmare energy of this place. It's born from one's negative emotions, particularly those of the sinful nature. Anger, hatred, greed, jealousy—things like that. It's fine on small amounts, but you get in trouble when you develop a lot of it and become consumed by those thoughts. Once it escalates to something like murder and obsession and you lose sight of all your human reason and morals, then you become corrupted and become a daemon. A lot of people take on more monstrous forms, but it's possible to still maintain one's will even after you turn.

Every living creature including animals can develop it. Only beings that can't are malakhim, or spirits in my world. They're more pure or something like that, but they can be tainted by our malevolence and turn into dragons.