Jack carries the many usual qualities of a stereotypical British-villain. He's got grace, and seems benevolent but sees himself as being "above others". He leads his men with a strict arm, and manages to keep them in order despite many of them being cowards, or having the usual mercenary attitude.
His ideals are rooted in profit, and greed, as everything he does inside the Schwarzwelt is done for the sake of money: Creating a demon army, and scavenging materials. He allies with the Red Sprite crew only as far as it serves him, and will betray them when business deems it.