This story features many original characters and elements that differ from canon. It is a derivative work based on the American animated series Helluva Boss and Hazbin Hotel. Minors should not read it. If it's not your thing, don't read it.
Brennan has lived two lives, yet he and Caspian, an upperclassman who also came from another world, both died in a school shooting abroad and fell into Hell.
Hell looks remarkably like a human city, except for its strange inhabitants. Brennan has become a white-haired werewolf demon with scarlet eyes, while Caspian has grown pale blue butterfly wings and become a humanoid butterfly demon.
Having survived a gang shootout during his human life this time around, Brennan pursues the desires he carried from his previous life and approaches Lord Husk. Caspian, who once kept a wealthy woman during his human life, wants to find a "proper job" instead. By chance, he gains the service of a group of demons and begins his rise to becoming a Lord of Hell.
Two souls from another world, each carrying their own sins and obsessions, adapt quickly to their new demonic identities in this world where Hazbin Hotel and Helluva Boss intertwine, while searching for a new life in Hell.
To add some knowledge, it has been confirmed in the second season of Hell Inn that Alastor is actually Rossi's servant and pet. Alastor's power comes from the cannibal lord Rossi. Lucifer gave Alastor a few words to say that he had broken his guard and resigned. His going to the inn and the seven years he disappeared were all ordered by Rossi.
It's really beautiful