What is the difference between demons and humans? Without the explanation of the word "human", then it is a demon. There is no special reason and no special reason is needed.
It's that simple, it's that simple, it's so mindless.
The flame called resentment in the heart quietly lit up. Was it cursed by the devil or the incarnation of the devil? Anyway, the seeds of the devil had been quietly buried in the hearts of the two brothers. The two of them licked each other's wounds, preventing others from hurting them over and over again.
This thing has been with them since they were born.