Sebastian Haven was not the type of person to wish ill on anyone. Many of his associates, when he told them this, often laughed, thinking that he was joking, because Sebastian was known to be quite vindictive. But he was actually telling them the truth.
He really was not the type to wish ill on any other human being. And the reason for that was simple. If Sebastian wanted something bad to happen to you, he did not wish it upon you. He simply got up, and made the awful fate that he wanted to befall you, become a reality.
He was not above spreading rumors to ruin a reputation. Poisoning was something he did on the regular. Blackmail and assault as well as harassment were some of his favorite friends.
As a result of being such an active go out there and do it yourself person. Sebastian had always been of the mind that people who wished ill on others, but could not go through with it were lazy, spineless cowards that needed more motivation.