Lt. Pug is the commanding officer in charge of the Bark Brigade, though this is due to the fact that the other available officers capable of running the Bark Brigade have reasons that prevent them from doing the job. While the Bark Brigade has not been too large, it received a sudden boost to membership when Roger and Anita Dearly moved in with their 101 Dalmatians, which left Pug with the task of forging them into proper cadets and instilling in them the knowledge they will need to survive in the world. However, he prefers to do such in a fashion that berates the cadets, as he has a personal fear of having his authority being questioned, so he scolds his cadets at every chance he gets in order to remind them who is in charge. Despite his many flaws, Pug does his best to make the Bark Brigade as efficient as possible, and he has the respect of many individuals on the farm, though his cadets often disrespect him due to the fact that he is unnecessarily harsh towards them during the Bark Brigade training sessions.
However, Lt. Pug does have one innate flaw that jeopardizes his future in the Bark Brigade and his chance for advancement: he has an innate fear of cats. Due to the fact that he was abused by a large cat, Persian Pete, when he was a child, Pug believes that all cats are the enemy and that they are secretly working together to plan an invasion that would result in all dogs being enslaved. Pug has included this fear in his Bark Brigade instructions, as he wishes to train his cadets to be ready for the day when the cats invade, though the Dalmatians think he is crazy, especially since a cat serves as an officer in the Bark Brigade, and that he has earned the trust of the Dalmatians. Pug also suffers from narcolepsy, and often falls asleep during important situations, or when he is in the process of scolding his cadets, though he tends to wake up from these stints after several minutes. Pug refuses to put up with nonsense, and despite the fact that he is paranoid and overly harsh, whenever there is a problem on the Dearly Farm, the citizens know that they can rely on Pug to get things sorted out.
Pug has a stuffed rabbit named Private Bunny that acts as security measures to him; if anyone messes with it, Pug will take action. A running gag throughout the series is Pug mispronouncing the Dalmatians' names.