Oliver carried out his orders efficiently. All the slaves who served as guards were men who had fought in one way or another, either in wars or alone, for that reason they knew death closely.
Being men of combat and experience despite not being the most powerful, they had the right mentality and disposition to comply with orders as sadistic and cold as if they were normal things.
In fact, these orders in situations and businesses like this in this world really were normal, unlike Andrew's previous world where there was better control of public safety, this world was quite lacking.
To be more exact, it was not that they did not have the capacity to improve this situation, but that there were many interests and money involved and that is why the high spheres of power turned a blind eye, that is why the appearance of one or two corpses in the river once in a while was not too strange.
