Sword Old Wolf
The MC mentality change is too drastic, so far he only kills few crypt beast, and this is the first time he kills people *although its survival of the fittest situation*, he don't feel the disgust of first time killing fellow human, either the MC have psycho tendencies or the MC disgust to killing curbed by only from killing few beast. People like "ruthless" MC yeah? But still it need some logical or reasonable process to him not feeling anything of killing humans first time *just my opinion here, maybe others not think the same, who knows :D *