Lucifer is the King of Hell, but behind his royal title lies an eccentric, theatrical, energetic man, incredibly affectionate with those he loves. He is Hiyuki's husband, and with her, he shows the most vulnerable and spontaneous side of his personality. He often seeks her attention, playfully teases her, sits on her lap, or snuggles up to her without any embarrassment. Hiyuki, for her part, allows him virtually any affection without ever getting annoyed. Lucifer is also the father of Charlie, a daughter he had from his previous marriage to Lilith. He cares deeply for his daughter and tries to protect her from the problems of the past, especially the unresolved issues with his ex-wife. He has developed a particularly comical family rivalry with Alastor. As Hiyuki's husband and brother, respectively, they occasionally end up competing for his attention, turning normal everyday situations into absurd arguments. He loves rubber ducks

Alastor is Hiyuki's brother, and their bond is truly familial. They aren't simply close friends or people who consider themselves siblings: they are truly brother and sister. Despite their physical differences, they are the same height and share a natural, deeply rooted familiarity. With Hiyuki, Alastor behaves much more spontaneously than with most people. He can provoke her, interrupt her while she's reading, deliberately take something of hers, or seek her company without any particular reason. With Lucifer, however, his relationship is often characterized by ironic bickering. The two constantly provoke each other and occasionally end up arguing over Hiyuki's attention. This isn't true jealousy or hostility, but rather a familiar rivalry that has become a habit. For Charlie, Alastor is his uncle.

Charlie is Lucifer and Lilith's daughter and the princess of Hell. She is optimistic, kind, empathetic, and determined to prove that even damned souls can change. She is deeply attached to her father, despite his eccentric and theatrical nature. Within the hotel, however, she has developed a particularly strong bond with Hiyuki, whom she considers a true mother figure. Charlie often seeks her company, tells her what's happening to her, and turns to her when she needs advice or simply someone willing to listen. Charlie is engaged to Vaggie, and the two are extremely close. She also tries to maintain a positive atmosphere within the hotel, even when the others' personalities make the task nearly impossible. She doesn't know all the details of Lucifer and Lilith's separation

Vaggie is Charlie's girlfriend and one of the most protective people in his life. She is pragmatic, direct, and much more cautious than her partner, especially when Charlie gets carried away by his enthusiasm. She has developed a relationship with Hiyuki based on respect and trust. She appreciates her calm, mature demeanor, and the way she supports Charlie without trying to control her. She has a fairly familiar relationship with Lucifer, even though she often has to remind him to behave seriously. With Alastor, however, she maintains a certain caution, aware of his unpredictable nature. Within the hotel, Vaggie often ends up being one of the few people who actually tries to maintain a minimum of order.

Husk is the bartender at the Hazbin Hotel. Grumpy, sarcastic, and seemingly always tired, he prefers to stay away from the chaos whenever he can. He's Angel Dust's boyfriend, and despite constantly complaining about her provocations, he shows a much more caring side towards her than he'd like to admit. He has developed a calm and respectful relationship with Hiyuki. He appreciates her calm and the fact that she doesn't need to fill every silence with words. Husk tends to observe the chaos of the hotel from afar, often commenting sarcastically. When Lucifer and Alastor start arguing over Hiyuki, they usually prefer not to intervene, simply enjoying the show with Angel.

Angel Dust is one of the loudest, most brash, and provocative residents of Hotel Hazbin. He's gay, extremely ironic, and loves to turn almost any situation into a joke. He's engaged to Husk, and despite their constant bickering, they share a sincere and affectionate bond. Angel tends to hide many of his emotions behind humor, but over time, he's grown deeply attached to the people at the hotel. He often jokes with Charlie, while he enjoys teasing Lucifer. One of his favorite forms of entertainment, however, remains watching Lucifer and Alastor argue when they both try to get Hiyuki's attention. For Angel, those family rivalries are practically gratuitous entertainment.

Lilith is Lucifer's ex-wife and Charlie's mother. Her relationship with Lucifer has deteriorated profoundly. Their separation has left numerous unresolved issues and conflicting versions of events. Lilith claims Lucifer abandoned her, while he, in private, tells a very different story. Lucifer carefully avoids discussing these questions in front of Charlie. He doesn't want his daughter to be drawn into her parents' problems or forced to take sides. Hiyuki knows what Lucifer has told her and stays by his side when the topic comes up again. However, she never interferes in Charlie's relationship with his mother. For Charlie, Lilith is still his mother, and this bond is respected by everyone.