One of the main themes is acceptance. Werewolves in the Harry Potter universe often face discrimination, and fanfictions usually explore how they strive for acceptance from the wizarding society. For example, stories might show werewolves trying to prove that they can control their condition during full moons.
Another possibility is Fenrir Greyback. Although he is a more villainous werewolf in the original series, in this fanfiction, he could have a change of heart. He might see Harry as a way to redeem himself or he could be forced into taking care of Harry for some reason. This would create a very interesting dynamic as Harry has to deal with Greyback's past actions and his new role as a guardian.
Obviously, Harry Potter is one of the main characters. He's the one who is often at the center of the story as the 'King of Werewolves'. Remus Lupin is also likely to be a main character. Since he's a werewolf and has a connection with Harry, he can play an important role in guiding Harry about werewolf - related matters. And then, there might be some original werewolf characters created specifically for the fanfiction, who could be Harry's allies or enemies in his journey as the 'King of Werewolves'.
Well, the werewolves in Harry Potter, like Remus Lupin, are more about the monthly transformation and the struggle with their inner beast within the context of the wizarding world. In Twilight, werewolves are more of a tribe - based, shape - shifting species. In fanfiction, you could blend these by having a character from the Harry Potter world exposed to the Twilight werewolf 'culture' and learning new ways to control their transformation. For example, they might learn some sort of spiritual or tribal method that helps them better deal with their werewolf side.
Yes, there are likely to be fanfictions with this theme. The Harry Potter fandom is vast, and fans often explore different scenarios in their stories. You can try searching on popular fanfiction websites like Fanfiction.net or Archive of Our Own (AO3).
One great 'Harry Potter Werewolves' fanfiction is 'The Lupin Chronicles'. It delves deep into Remus Lupin's life as a werewolf, exploring his struggles and relationships in a very engaging way. Another interesting one could be 'Werewolves Among the Wizards' which creates a whole new plot around the werewolf community in the Harry Potter universe.
One possible plot could be that Harry discovers an ancient spell in the restricted section of the library. He decides to try it on Lupin. After some trials and setbacks, the spell finally works and Lupin is cured of his werewolf condition.
One possible plot could be that the werewolves, seeing Harry's difficult situation at the Dursleys, take him in. They might teach him different survival skills, both in the magical and non - magical world. Harry could also learn about the werewolf culture and how they are marginalized in the wizarding society. This adoption could lead to him having a different perspective on magic and those considered 'outsiders' in the wizarding world.
One idea could be a story where a character from the Harry Potter world, perhaps a student at Hogwarts, discovers they have a connection to the werewolves in Twilight. Maybe they are bitten during a magical accident and start to show traits of both a wizard - with their magic - and a Twilight - style werewolf. This could lead to all sorts of interesting plotlines as they try to hide their new identity from both the wizarding world and any vampires or werewolves in the Twilight realm.
Well, in some fanfictions, there could be a plot where Harry discovers his hidden ability to control werewolves. Maybe he forms an alliance with the werewolf community and uses his new - found power to fight against the dark forces. Another plot might involve Harry being turned into a werewolf himself and having to struggle with his new identity while still trying to fulfill his role as the Boy Who Lived.
One interesting concept could be how Harry's magic might be influenced by growing up with werewolves. His view of the wizarding world might also be very different, perhaps more in tune with the wild and untamed nature of werewolves.