A plot could involve the Hazbin Hotel trying to rehabilitate the Doom Slayer, thinking he's just another lost soul. But the Doom Slayer has his own mission and doesn't understand the concept of rehabilitation. This leads to a lot of misunderstandings and conflicts. Meanwhile, some of the more evil demons in the hotel's world see the Doom Slayer as a threat and try to take him out.
One possible plot could be that the Doom Slayer somehow gets teleported to the Hazbin Hotel universe. He then has to deal with the demons there, which are different from the ones he usually fights. The hotel staff might initially be afraid of him, but then realize he could be an asset in dealing with more malevolent demons.
The plot could start with a strange anomaly that links the two universes. The Doom Slayer enters the Hazbin Hotel world and starts wreaking havoc as he mistakes the demons there for his usual enemies. Charlie, the main character in Hazbin Hotel, tries to calm him down and explain the situation. As the story progresses, they might team up to fight a greater evil that is threatening both their worlds. This could involve exploring the different power dynamics and moral compasses of the two sets of characters, as well as how they adapt to each other's presence.
One possible plot could be that the Doom Slayer somehow ends up in the Hazbin Hotel universe. He might initially be seen as a threat due to his violent nature. But then, they realize he could be an asset in dealing with some of the more dangerous demons in the Hazbin Hotel world. For example, he could help Charlie and her crew deal with some of the more unruly and powerful demons that are causing trouble in and around the hotel.
There are a few out there. However, the quality can vary a great deal. Some fanfictions might be more action - oriented, with the Doom Slayer getting involved in the chaotic world of Hazbin Hotel, perhaps fighting against some of the demons there in his own brutal style. Others could be more about character relationships and how the two very different characters from different franchises would get along or clash.
Maybe the Hazbin Hotel is in the middle of a crisis where the souls of the damned are being consumed in a strange and new way. Charlie and her crew suspect it has something to do with a portal that has opened up to a dimension filled with the kind of demons the Doom Slayer is used to fighting. They seek out the Doom Slayer, who has to navigate the politics and oddities of Hazbin Hotel's Hell while trying to close the portal and stop the consumption of souls.
One possible plot could be that the Doom Slayer somehow gets transported to the world of Goblin Slayer. He then uses his advanced weaponry and combat skills to help the Goblin Slayer in his never - ending fight against the goblins. Maybe they team up to take on a super - powerful goblin boss that neither could defeat alone.
One possible plot could be that some of the Hogwarts students accidentally end up in Hell (the setting of Hazbin Hotel). They could encounter the characters from Hazbin Hotel and have to find a way to get back. Maybe they initially think it's a part of some new magical realm or a powerful dark wizard's creation. For example, Harry Potter, Hermione, and Ron could meet Charlie and learn about her plan to rehabilitate sinners. The Hogwarts students might be skeptical at first but then start to see some similarities between the way magic is used in Hell and at Hogwarts.
Well, the plot could involve a rift opening between the two worlds. Goblins start pouring into the Doom world and the Doomguy has to deal with them. Meanwhile, the Goblin Slayer follows the goblins through the rift and they end up working together to close the rift and stop the chaos. They might exchange combat techniques and learn from each other's experiences along the way.
One possible plot could be that the Doom Slayer gets transported to the Chainsaw Man universe. He teams up with Denji to fight against a new type of demon that is a combination of the demons from Chainsaw Man's world and the hellish creatures from the Doom universe. Their combined strength and different fighting styles make for an epic battle.
Another interesting interaction could be between Vaggie and the Doomguy. Vaggie is protective of Charlie and the hotel's mission. When she meets Doomguy, she might be suspicious of his motives. She could be constantly on guard around him, and he might be a bit annoyed by her over - protectiveness. Their relationship could start off as very tense but could develop in interesting ways as they get to know each other better.
Well, perhaps in this fanfiction, the characters from Hazbin Hotel end up in the Naruto world. Charlie could see the problems of the shinobi world, like the discrimination against the jinchuriki, and try to bring her ideas of redemption to the place. Meanwhile, Naruto could befriend the Hazbin characters and learn about their unique powers and backstories, leading to a cross - universe adventure.
In a 'doom slayer in another world fanfiction', perhaps the Doom Slayer is transported to a post - apocalyptic world different from his own. Here, he has to adapt his fighting style to new threats. He could discover new ways to upgrade his weapons using the resources of this strange world. Maybe he even has to face a new kind of demon that has evolved in this different environment.