Emerald Grand Duchy was ruled by the vampires, but the Duchy's law and order were very good. It was considered superior to other grand duchies.
Emerald Grand Duchy did not have any local gangsters. Most of the inhabitants were commoners with a small number of slaves. The crime rate was low, and the number of evil warlocks was also few.
The vagabonds in the duchy were all drained of blood by the vampires…
That was the reason why the Human empires and kingdoms were not bothered with these issues even when they knew that the leaders of Emerald Grand Duchy were vampires.
The Human empires were more concerned about the strategic view of the world. Humans could easily kill the vampires who were officials of the grand duchy any time, and they were not afraid of the Blood Dragon, the ancestor of the vampires.
Hence, Humans could not be bothered by the mediocre vampires. They thought of them as sheep that could be killed anytime.