It could be alternate versions of the villains from their own universe. For instance, an alternate Voldemort who is even more powerful. Maybe there are also new characters who oppose Harry and Teddy just because they are outsiders in this alternate universe.
In the fanfic, it's possible that the very structure of the alternate wizarding world is the antagonist. The laws and customs there could be so different and oppressive that Harry and Teddy have to constantly fight against them. And, of course, there could be an alternate version of someone like Bellatrix Lestrange who is even more cruel and bent on destroying them.
In this fanfic, they might encounter alternate versions of themselves. For example, Harry could meet a version of himself who is a dark wizard instead of a hero. Teddy, with his shape - shifting ability, could have a hard time adjusting to the new universe where the rules of magic might be different. They may also find new magical creatures that don't exist in their original universe and have to figure out how to interact with them.
Obviously, Harry and Teddy are the main characters. Harry is a well - known wizard from the original series, and Teddy is his godson.
It's hard to say without more details about the fanfiction. But it could be some characters who benefit from Teddy not having rights, like power - hungry individuals or those with prejudiced views.
A Hufflepuff prefect could be the main character. They are responsible for maintaining order within the house and could be caught in the middle of a power struggle between the different houses in this alternate universe. They would have to use their Hufflepuff traits to resolve conflicts and keep the peace in Hogwarts.
Perhaps he meets a version of his parents who are still alive. This would be an incredibly emotional encounter for Harry. He would get to know them, and they could teach him things about magic and life that he never had the chance to learn before.
In this 'naruto alternate universe naruko fanfic', apart from Naruko, Kakashi could be a significant character. He might be Naruko's mentor, guiding her through her ninja training. And Hinata could be another main character. Maybe she has a special connection with Naruko, like they are on a joint mission to protect the village from a new threat. Additionally, there could be new characters created specifically for this alternate universe who interact closely with Naruko.
Well, Hermione is often depicted in different ways in these fanfics. In some alternate universes, she could be a powerful dark witch instead of the studious and good - hearted character we know. Ron might be a super - confident and arrogant character rather than the sometimes insecure boy in the original story. Also, Snape could be a completely different person. He could be a jolly and friendly teacher rather than the brooding and complex one we are used to.
Severus Snape is a fan favorite in alternate universe stories. People are interested in seeing his character developed further, perhaps in a world where he didn't have such a complex relationship with Lily Potter. Harry Potter himself is, of course, a popular choice. Fanfic writers might create scenarios where Harry discovers his magic much earlier or has different adventures outside of Hogwarts that change his character development.
The main characters are Harry and Teddy, but don't forget about the wizarding community around them. There could be other minor characters such as Teddy's teachers at Hogwarts when he gets older. They would play a part in Teddy's development, and Harry would interact with them to ensure Teddy has a good educational experience.
In most teddy harry potter fanfic, Teddy Lupin is at the center. But other characters like Hermione Granger could also play important roles. Maybe she helps Teddy with his studies or gives him advice. And Ron Weasley could be there too, adding some humor to Teddy's adventures. Also, characters from Teddy's family, like his grandmother Andromeda, might be included to show his family background and support system.