For me it's Shinji Aoba.
I am sociopath. Years of torment have turned me into the monster I am today. At this point I am far beyond help. My only purpose in this world is to bring pain to others. I have trained my skills to cause maximum havoc and destruction. I care about nothing and have nothing to live for, this is what makes me so dangerous. I am like a caged animal. Actually more like a rabid dog because I will not hesitate to destroy anything that slightly provokes me