Yamazaki has psychopathic tendencies with a love for materialistic articles and money. He is the calm and confident gangster at one time, and a hysterical killer in another. He likes to bash, smash, cut, and kill everyone and anyone whom he confronts. These savagely cruel mannerisms were borne out of witnessing his father figure die in the worst way possible.
While not completely amoral, he is not above toying around as much as he likes to emphasize his dominating demeanor to anyone he encounters.
Of curious note is how Yamazaki subconsciously keeps his right hand in his pocket because his idol once praised the power of that particular fist, and only uses it for special techniques.