Often, there are advisers or mentors. These are characters who have a lot of knowledge about the monarchy and its workings. They might be old nobles or wise scholars who help Harry understand the ropes of being the heir. There could also be antagonists like power - hungry nobles who see Harry as a threat to their own ambitions and try to get rid of him.
Another common type of character could be his friends. They could be from different backgrounds, some from the aristocracy and some from more common origins. His friends could offer him different perspectives, and in some fanfictions, they might be involved in adventures or schemes with Harry, either helping him on his path to the throne or causing some trouble that he has to sort out.
Hermione is often a common character. She would probably be by Harry's side, using her vast knowledge to help him understand his role as the Gryffindor heir. Ron might also be there, providing his loyalty and comic relief in tense situations.
Ron could also be there. He might be a bit jealous at first if Harry's adopted family is wealthier or has more influence in the wizarding world. But later, he would support Harry as always.
Hermione could still be a common character. Even in fanfiction where Harry is alone, Hermione might be mentioned in his thoughts or in flashbacks as someone who has influenced him. For example, he might recall her advice on how to study magic when he is facing a difficult spell alone.
Draco Malfoy is a very common character. Since they are in the same house in this fanfiction concept, their interactions would be different from the original story. There would likely be more opportunities for them to either become friends or rivals in a new way.
There could be some original characters created by the fanfiction authors. These could be Harry's new classmates or friends at Durmstrang. They might have their own unique magical skills and personalities, and through their interactions with Harry, they can help develop the story further. For example, a new friend could introduce Harry to a secret part of the Durmstrang grounds or a special magical technique that's unique to the school.
Ron could also be there. He'd bring his sense of humor and loyalty. Maybe in a story set in Australia, Ron would be the one to make friends with the local magical folk first because of his easy - going nature, and then introduce Harry to them.
Dumbledore might also be a common character. He could serve as a guide or mentor to Harry in his new role as heir, providing wisdom and advice. Additionally, some fanfictions might include characters from the Potter family's past, like his parents James and Lily, who could appear in flashbacks or as some sort of spiritual guidance for Harry.
Well, of course, Harry Potter himself is a common character as the heir in these fanfictions. Hermione is often there too, helping Harry figure out the implications of his new status. Ron may also be present, providing support and some comic relief. Sometimes, characters like Dumbledore play a key role as well, guiding Harry through the revelations about his heritage.
Hermione is often a common character. She would be there to support Harry in his journey as the heir, using her vast knowledge of magic to help him understand the implications of his new status.
Ginny Weasley could be another character. Given her relationship with Harry in the original series, in the fanfiction she might be part of the harem, bringing her own strong - willed and talented self into the mix, and her experience with the Weasley family's magic and values could influence the group.