There could be a story where Fenrir Greyback, instead of being an enemy, is a potential ally due to some strange magical bond that forms between him and Harry Potter. This bond might be the result of a powerful spell gone wrong. They then have to navigate the wizarding world's reaction to their new relationship while also trying to figure out how to use this bond to defeat the greater evil of Voldemort. Fenrir might provide Harry with some unique insights into the darker side of magic that he didn't know before.
A plot could involve Fenrir being cursed in a way that makes him lose his werewolf - like aggression and he seeks help from Harry Potter, who is known for his kind heart. Harry initially distrusts him but then realizes Fenrir's genuine need for help. Or perhaps they are both caught in a time - travel spell and end up in a different era where they must rely on each other to get back to their own time, while also dealing with the challenges of that new time period.
One plot idea could be Fenrir Greyback being forced to work with Harry Potter to defeat a common enemy. Maybe a dark wizard who is more dangerous than Voldemort is threatening both the wizarding world and the werewolf community. This would put them in an uneasy alliance, with Harry having to trust Greyback not to turn on him.
A really interesting plot could be set in an alternate universe where Fenrir Greyback was once a normal wizard but was turned into a werewolf by dark magic. Harry Potter, through some magical accident, finds himself in Greyback's past and tries to prevent his transformation, which would change the course of the entire wizarding world as they know it.
One idea could be that Fenrir Greyback, instead of being a full - on villain, has some sort of complex relationship with Hermione. Maybe he's forced to protect her in a situation where they are both in danger from a greater dark force. This could lead to a lot of tension and moral dilemmas for Hermione as she has to deal with being around a werewolf who has a reputation for being cruel.
One plot idea could be that Fenrir Greyback, instead of attacking Hermione, is somehow magically bound to protect her. This could lead to a strange alliance where Hermione has to trust a werewolf known for his brutality. Another idea is that Fenrir has a change of heart due to Hermione's intelligence and courage, and he starts to fight against his dark nature for her sake. Maybe he could help Hermione in a battle against the Death Eaters by using his werewolf strength in unexpected ways.
One interesting plot could be Fenrir Greyback trying to turn Harry Potter into a werewolf as a way to get back at Dumbledore or the Order of the Phoenix. He might see Harry as a symbol of the resistance against the Dark Arts and wants to corrupt him in the worst way possible.
A possible plot is that Hermione, in her pursuit of equal rights for magical creatures, decides to reach out to Fenrir Greyback. At first, he is hostile, but Hermione's determination and her ability to see beyond his monstrous side start to change him. They could end up in a situation where they have to work together to stop a greater evil that is targeting werewolves and other marginalized magical beings. This would involve Hermione using her logical thinking and Fenrir using his knowledge of the werewolf underworld.
Fenrir Greyback is significant in Harry Potter fanfiction as he represents a different kind of evil compared to the main antagonists. He's more primal. His actions are often driven by his werewolf instincts. In fanfics, this can be used to create unique horror - themed storylines where characters have to face not just a dark wizard but also a savage werewolf.
Fenrir Greyback in fanfiction can also be a way to explore the werewolf sub - culture in the Harry Potter world more deeply. Some stories might focus on how he influences other werewolves, whether he's a leader or a lone wolf (no pun intended). His character can be used to show the discrimination that werewolves face in the wizarding world, as he's such a violent example of one.
One plot idea could be that Fenrir, in his 'good' form, helps Hermione in her research on werewolves. He uses his insider knowledge to guide her in understanding the complex nature of lycanthropy, and they form an unlikely alliance against those who want to use werewolves for dark purposes.
Well, in some fanfictions, Harry being bitten by Fenrir Greyback could lead to a change in his relationships. His relationship with Dumbledore might become more complex as Dumbledore tries to guide him through this new and dangerous situation. Also, it could potentially create a rift between him and some of his classmates who are afraid of his new werewolf nature.