Azazel manifests as a canine-featured demon sporting leathery bat wings, satyr legs, and a distinctive orange bowlcut hairstyle. His standard form features a prominent pot belly, man-boobs, and an emotionally reactive necklace strung with three tiny humanoid skulls. He transforms into a muscular, human-sized satyr with horns and slicked-back hair for his hell form, wielding an oversized fork. Despite his demonic traits, human world observers frequently mistake him for a mere dog.

He embodies the sin of lust, exhibiting a perverted and mischievous disposition. This manifests as persistent sexual harassment, particularly targeting his summoner Sakuma, and a constant stream of lewd jokes. Prone to laziness, he actively avoids work and responds to setbacks with theatrical wails or complaints. Despite his demonic nature, he displays significant cowardice, especially concerning his former summoner Akutabe, who physically punishes him for failures or disobedience. Azazel occasionally demonstrates loyalty to fellow demons like his childhood friend Beelzebub, though he typically treats others with open contempt.

His primary power, "Lewdness," manipulates lust-related aspects within living beings. This enables him to incite or suppress sexual attraction, induce impotence, and identify lustful desires. His ultimate technique, "End of Son," concentrates perverted energy into a destructive sphere that eradicates lust in targets—though repeated use risks backfiring, amplifying the target's power. Executing this move severely drains him, necessitating exposure to pornography for recovery. He also wields a combat trident named "Sexcalibur," its full capabilities undefined.

Originally summoned and controlled by the detective Akutabe, Azazel endured constant physical punishment for underperformance or misbehavior. Following Akutabe's termination of their contract, Azazel formed a new pact with Sakuma, Akutabe's assistant. Their relationship involves frequent clashes stemming from his harassment of her, though she gradually adopts more manipulative and morally ambiguous traits under his influence. His personal life includes a tumultuous relationship with Kiyoko, a pink dog-like demon convinced they are married due to their physical encounters; she subjects him to domestic abuse. His background reveals poor academic performance in demon school and a reputation for mediocrity in his duties, often relegated to menial tasks like window cleaning.

Throughout his narrative, Azazel oscillates between causing chaos and providing reluctant assistance in supernatural cases. His hell form suggests latent potential beneath his habitual comical ineptitude. Encounters with entities like angels collecting demon grimoires or high-ranking demons such as Moloch underscore his low status within hell's hierarchy. While showing minimal overarching development, his dynamic with Sakuma exhibits subtle shifts; her increasing ruthlessness sometimes compels his cooperation, though his actions remain fundamentally self-serving.