Sloth, also known as Lord of the Flies, is a member of the Seven Deadly Sins that were originally imprisoned by the Four Horseman many centuries before the Apocalypse. However, upon the End War's premature onset and the destruction of humanity, Sloth, along with his brethren, were freed and began to ravage the Earth and threaten the Balance.

True to his name and title, Sloth has absolutely no desire to do anything but sit upon his throne and let his insect slaves do everything for him. Even the decision to choose is considered tiresome and boring to Sloth; thus he prefers to not choose at all. He doesn't even care if his fellow Sins. Sloth is incredibly cynical, finding life itself a joke and the ideas of Balance and dignity to be a myth. Ideals that people follow to make themselves feel better, to give themselves purpose.