Dennis has medium-length messy brown hair and slight stubble. He also has tannish-colored eyes. He wears the standard Military Police uniform.
Dennis is a lazy, laid-back, high ranking Military Police officer. Like many of the soldiers outside the Survey Corps, before and after the fall of Wall Maria, he would rather spend his time on the clock drinking and gambling. When given the opportunity he quickly shirks his duties onto those below him in rank.
Dennis was in charge of overseeing the mission to escort Eren Yeager through the town, but later handed this over to Marlowe Freudenberg when the latter questioned the operation's details. It is revealed shortly after this happens that he shirked his duties to his subordinate in order to gamble, drink, and play cards instead.