| addict slayer
| nihilist pacifist
(y = desire to kill, x = desire to live)
So, the sociopath starts out as a machine. As he loses power, he drifts towards nihilism. But then, as he is starting to love and desire life, his lover is threatened. He returns to killing but later repents and becomes a pacifist. Finally, he is needed to be a hero and returns to reluctant killing as a warrior.