Well, Severus Snape made so many sacrifices throughout the Harry Potter series. He risked his life constantly to protect Harry, yet he was often misunderstood. In fanfiction, authors try to rectify this. They want to show a world where his selfless deeds are fully recognized and he gets the rewards he should have had, like real friendship and peace. For instance, he could have a story where he finally gets to teach without all the political drama in Hogwarts, or he could have a loving relationship that he was deprived of in the original. It's about giving him a more positive and fulfilling existence.
One great fanfiction could be 'The Redemption of Severus Snape' where it delves deeper into his backstory and gives him a more fulfilling and peaceful ending. Another might be 'Snape's Second Chance' which allows him to have more positive interactions with the other characters after the war. And 'Severus Unbound' that frees him from some of the harsher constraints of the original story and lets him find true happiness.
People write it because Snape is such a complex character. His leaving in the original story leaves a lot of room for speculation. Writers want to fill in the gaps about what he might do next, where he might go, and what his future holds.
Yes, in some fanfiction, Severus Snape is depicted as a vampire. Fanfiction allows for creative interpretations of existing characters, and making Snape a vampire can add an interesting and often dark twist to his character.
There could be a sense of wanting to rewrite the narrative. Maybe they felt that Snape was over - glorified in the original story, especially considering his past as a Death Eater. They want to explore the idea that his actions, even his good ones like protecting Harry, were not enough to make up for his earlier wrongdoings. So they write fanfiction to challenge the positive view of Snape that some fans have.
In some fanfictions, Snape has badass moments when he outsmarts Voldemort. For example, he manages to mislead Voldemort about the location of a crucial magical artifact. He uses his Occlumency skills to his advantage, hiding his true thoughts and intentions while presenting false information in a very clever way. This not only shows his intelligence but also his courage as he risks his life to deceive the Dark Lord.
In these fanfictions, Snape often becomes more self - reflective. He starts to realize the full extent of his actions and how they've affected others. For example, he might come to see how his treatment of Harry was unfair. He also becomes more open about his emotions, which was something he always hid before.
At the start, Snape would likely be quite suspicious of Naruto. He's used to a world full of secrets and might think Naruto is some sort of threat or spy. Naruto, being Naruto, would keep trying to break through Snape's cold exterior. He might start by complimenting Snape's skills in potions or magic. As time goes on, Snape might see Naruto's good heart and start to open up a bit more. They could end up having some interesting conversations about power, loyalty, and friendship. Naruto could tell Snape about his bonds with his friends in the ninja world, and Snape could share some of his own experiences with the Marauders from his school days.
Well, Harry Potter would likely still be a main character. His relationship with Snape could be even more complex in this fanfiction. Since Snape is a demigod, Harry might be both in awe and a bit scared of him at times.
One great Severus Snape centric fanfiction is 'The Prince's Redemption'. It delves deep into Snape's past, exploring his relationship with Lily before Hogwarts. It shows how his love for her shaped his actions throughout his life.
One great Severus Snape werewolf fanfiction is 'The Lupine Professor'. It delves into a world where Snape has an unexpected encounter with a werewolf situation. Another interesting one could be 'Snape and the Moon's Curse' which has a really engaging plot about Snape's relationship with werewolves in the wizarding world.