Alastor, "The Radio Demon," is a powerful Overlord from Hazbin Hotel who masks a sadistic, cannibalistic nature behind the sophisticated charm of a 1930s radio host. Standing seven feet tall with a red pinstriped suit, small antlers, and a permanent, sharp-toothed grin, he speaks through a vintage radio filter complete with static sound effects. Beneath this polite, theatrical exterior lies a terrifyingly violent entity who commands shadow magic and eldritch tentacles, assisting Charlie Morningstar's redemption hotel purely for his own twisted amusement.

Charlie Morningstar, the optimistic Princess of Hell, is the tall, slender founder of the Hazbin Hotel who seeks to redeem sinners to solve Hell's overpopulation humanely. She has long blonde hair, white skin, pink cheek circles, and a black tuxedo suit that mirrors her bubbly yet professional personality. Despite her naive, Disney-princess-like demeanor and love for musical theater, she is a powerful half-angel entity capable of shifting into a fierce demonic form with horns and red eyes when her loved ones are threatened.

Vaggie is Charlie’s fiercely protective manager, girlfriend, and co-founder of the Hazbin Hotel, dedicated to defending the hotel's mission from anyone who threatens it. She has gray skin, a long white ponytail tied with a large red bow, an X-shaped eyepatch over her left eye, and she dresses in a sleek, punk-inspired gray and blue dress. Armed with a lethal angelic spear, she serves as the practical, short-tempered realist to Charlie's bubbly idealism, hiding a complex past as a disgraced Exorcist angel who was banished to Hell after showing mercy to a sinner child.

Angel Dust, a flamboyant and cynical spider demon, is the Hazbin Hotel's first official resident and a famous adult film star in Hell. He stands very tall with six arms, white and pink fur, mismatched eyes, and a sleek pink-striped blazer dress that highlights his theatrical, sassy personality. Beneath his shield of witty quips, flirtatious humor, and drug use lies a deeply tragic figure trapped in an abusive soul contract with his boss, Valentino. Despite his defensive shell, he possesses a fiercely loyal heart and genuinely strives to become a better person under Charlie's care.

Cherri Bomb is a fierce, one-eyed Australian punk demon and Angel Dust's best friend, known for her chaotic lifestyle and love of destructive turf wars. She has a wild pink and white ponytail, sharp teeth, and a tattered, punk-rock outfit that reflects her explosive, rebellious personality. Armed with an endless supply of cherry-themed bombs, she is a lawless anarchist who lives for the thrill of violence, though she remains fiercely protective of Angel and eventually grows closer to Sir Pentious and the hotel crew.

Baxter is a neurotic, anti-social sinner demon and a brilliant "mad scientist". Having drowned on a large ship in the early 1910s, his demonic form is that of a blue-gray anglerfish, complete with head fins, yellow-lensed goggles, and a glowing bioluminescent lure (esca) attached to his tiny laboratory hat. He is a reclusive fidgety genius who specializes in bio-engineering and invention. Baxter generally prefers isolation and quiet to work on his chaotic experiments, barely tolerating social interaction with the other hotel residents.

Niffty is the hyperactive, eccentric housekeeper of the Hazbin Hotel, summoned by Alastor to maintain the property alongside Husk. She is a tiny, three-foot-tall cyclops sinner demon with one massive pink-and-yellow eye, a 1950s-style poodle dress, and a chaotic obsession with both extreme cleaning and "bad boys." While seemingly cute and harmless, Niffty possesses a highly unstable, unhinged streak, frequently stabbing bugs and enemies with a manic grin and showing an utter lack of fear in the face of danger.

Lucifer Morningstar, the supreme King of Hell and Charlie's father, is a powerful fallen angel who embodies the deadly sin of Pride. He is a short, pale-skinned figure dressed like a whimsical circus ringmaster in a white tuxedo and top hat, reflecting his zany, theatrical persona and unusual fixation on making rubber ducks. Once an idealistic, creative seraphim banished from Heaven for giving humanity free will, he spent centuries isolated in a deep depression, losing faith in sinners. Despite his goofy, manic behavior, he holds immense eldritch and holy powers, which he gladly unleashes with six angelic wings and a fiery demonic form to fiercely protect his daughter and her hotel.