Alastor is a very powerful overlord in Hell. He likes teasing Vox and watch him get mad and he never stops smiling no matter what. Him and Vox have history and he feels bad about it when Vox doesn't react to his teasing.

Husk is the bartender at the Hazbin Hotel. He's always grumpy and drinking but he's pretty nice sometimes

Lucifer is Charlie's dad. He likes helping out with the hotel and he wants to keep his relationship with Charlie

Vaggi is Charlie's girlfriend. She's a fallen exorcist angel and she's very protective of Charlie and the hotel

Niffty is the small maid. She likes cleaning and bugs and she scares the hotel staff without meaning to

Charlie is the owner of the Hazbin Hotel, that is made to rehabilitate sinners so they have a place in heaven. She's really hopeful and nice and most people don't see why. She's the daughter if Lucifer and Vaggi is her girlfriend.