Obviously, Harry Potter himself would be the main character. He is the one who is escaping the wizarding world.
Hermione might also be a main character. She could be either helping Harry escape or trying to convince him not to leave. Given her intelligence and loyalty, her role could be crucial in the story.
Obviously, Harry Potter himself. Hermione and Ron would most likely be there too, as his closest friends. Dumbledore might still play a role, perhaps as an advisor to Harry in his new position. And there could be new characters, like wizards and witches from other parts of the world who come to see the new king.
One possible plotline could be Harry finding a hidden portal that leads to a parallel magical world where he can escape the troubles of his own wizarding world. He might encounter new magical creatures and spells there.
Obviously, Harry would be one of the main characters. He's the one driving the revitalization efforts.
Harry and Ron are obvious choices. They have a long - standing friendship with Hermione, and their reunion would be filled with reminiscing and new adventures.
Obviously, Harry Potter himself would be the central character. He would be the one driving the story forward with his actions and decisions.
Hermione would be a very likely character to help. She's smart and resourceful, and she would use her extensive knowledge of magic to come up with a plan for Harry's escape. Another could be Hagrid. He has a big heart and he's always been fond of Harry. He could provide a means of transportation, like his flying motorcycle or a secret passage he knows of. Also, Sirius Black might be involved. He's Harry's godfather and he would do anything to protect Harry from his family, so he could be a key figure in getting Harry out of that situation.
Well, obviously Harry Potter himself is a main character. He is the center of most of these fanfictions as he takes on the role of the king of the wizarding world.
Hermione might also be a main character. She's Harry's clever friend and could be helping him plan the escape, using her vast knowledge of magic and spells. She might be the one coming up with the strategies to avoid detection and deal with any obstacles in their way.
Obviously, Harry Potter himself would be the central character. His friends like Hermione and Ron would probably also play important roles. They might be his advisors or the ones helping him carry out his plans. Dumbledore could also be a significant figure, even if only in spirit or through flashbacks, guiding Harry's actions as he tries to take over the world.
Obviously, Harry would be the main character. Since it's about him being a Saiyan. And I think some of his friends from the Harry Potter series might also be important characters, like Hermione and Ron. They could react to Harry's new Saiyan identity in different ways.