Although Hell is presumed to have other demons at his disposal, the Devil frequently calls upon Smeck to do his bidding. Smeck serves the Devil out of a mix of duty due to his demonic nature and fear of punishment. Nevertheless, Smeck's lackluster performance usually results in a beating, many of which he inflicts upon himself to spare the Devil the trouble. Despite this common mistreatment, Smeck is continually loyal to the Devil. This is reflected in one episode where, following God's advice, the Devil attempts to treat Smeck with kindness and respect. While he enjoyed the perks, such as going to a carnival, Smeck pushed the Devil to return to his former abusive self on the grounds that he wasn't "himself" otherwise.
Despite his incompetence, Smeck does manage many duties in Hell that the Devil fails to attend to or deliberately avoids, most notably the processing the condemned souls and the paperwork that accompanies it. He also has shown to dabble in torture, overseeing and instigating the drawing of a damned soul he consulted for advice in dealing with the aforementioned change in the Devil's behavior.
On a couple of occasions, however, it is implied that he may even be attracted to his boss. One such instance had them watching Bob and Donna's unsuspecting joy on a screen, during which Smeck attempted to get close to the Devil, "in a fraternal way, like the Greeks".
God, the Devil, and Bob
Like the Devil, Smeck seeks to push Bob towards condemning his own soul, ultimately bringing about the downfall of humanity. However, Smeck's tactics and methods are often far more limited and much less successful. While the Devil can shape-shift into all sorts of forms, Smeck is limited to basic alterations of his impish appearance. In one such instance, he tried to convince God's former girlfriend, Sarah, that He still wants to be with her-as part of a scheme to keep God occupied so the Devil could lead another attempted conquering of Heaven. However, his disguise was limited to a rope and a cheap set of halo and wings to make himself appear "angelic". His ways of trying to appear human are limited to wearing clothes and wigs in a glaringly obvious attempt to cover up his features.
Outside of this, Smeck is also prone to a lot of errors on his part. Despite getting a memo to give Bob boils, as per the classic curse, Smeck mistakenly gives Bob a lot of bowls, thus running up a bill at Williams-Sonoma. His failure to manage Hell properly also resulted in the creation of a somewhat idyllic golf course on what is supposed to be the Fourth Circle of Hell. As the Devil later tries to sway Bob from seeing his father, Smeck tries to destroy the wing of Bob's plane, in the vein of the gremlin of "Nightmare at 20,000 Feet". However, he is caught up in the heavy winds and blown away before he can do more than superficial damage. Nevertheless, he manages to remain as the Devil's most attentive and summoned lackey.