Alastor, widely known as the "Radio Demon," is one of the most infamous and powerful Overlords in Hazbin Hotel. In life during the early 20th century, he was a charismatic New Orleans radio host who secretly lived a double life as a serial killer. Upon manifesting in Hell, he rapidly rose to immense power by overthrowing older Overlords and broadcasting their screams across the realm. Tall, dapper, and styled with deer-like attributes—including small antlers, tufted ears, and sharp yellow teeth—he presents himself as a retro, theatrical gentleman in a pinstriped coat, complete with a monocle and a microphone cane. His speech carries an old-timey Transatlantic accent filtered through vintage radio static. Beneath his polite and theatrical demeanor lies a deeply manipulative, sadistic narcissist who views the suffering of others as pure entertainment. Alastor adheres strictly to a self-imposed rule of maintaining a constant, wide smile, believing a smile signals complete control and masks one's true weaknesses. He joins Charlie Morningstar's endeavor at the Hazbin Hotel claiming he wants to help, though his true motivation is simply to watch the residents fail for his own amusement. Driven by a desire for control and dark entertainment, Alastor balances charm and terror, hiding his true intentions behind an enigmatic smile.

Lucifer Morningstar, the King of Hell and father of Charlie in Hazbin Hotel, is a complex blend of angelic majesty, circus flair, and emotional vulnerability. In contrast to his terrifying status as the ruler of the Pride Ring and the highest power in Hell, Lucifer appears as a short, flamboyant figure styled like a 1930s ringmaster. He dons a crisp white suit with red accents, a high-collared shirt, and a white top hat adorned with a golden snake and a red apple—symbols of his pivotal role in humanity's original fall from grace. He possesses porcelain-white skin, rosy red cheeks, slicked-back blonde hair, and sharp, expressive yellow eyes that occasionally glow red when his immense angelic power manifests. Carrying an apple-topped cane, his regal yet eccentric attire mirrors both his showman personality and his connection to the forbidden fruit. Despite his theatrical demeanor and tendency to burst into extravagant musical numbers, Lucifer's vibrant exterior masks a deeply depressed and disillusioned soul. After being cast down from Heaven for his idealism and subsequently separated from his wife, Lilith, he slipped into profound isolation, filling his time by crafting thousands of rubber ducks. He harbors an intense bitterness toward humanity, viewing them as inherently flawed and beyond saving, which initially strains his relationship with Charlie and causes him to scoff at her dreams of redeeming sinners. However, beneath his cynicism lies a fiercely loving, if socially awkward, father. When pushed to action, Lucifer unleashes terrifying, god-like angelic magic, using his full strength to protect his daughter and stand by her vision for the Hazbin Hotel.