There could be an original character created specifically for this fanfiction. This character might be the one directly affected by the 'ghost of you', and through their story, we get to explore the new ideas and plotlines in this fan - made story.
Hermione might also be a main character. She's known for her intelligence and problem - solving skills. In this fanfiction, she could be trying to figure out the mystery behind the 'ghost of you' phenomenon, using her vast knowledge of magic and lore.
Hermione would likely still be a main character. She would probably be the one trying to research about Harry's half - ghost condition, scouring the library for any information on half - human, half - ghost beings in the wizarding world. She might also be the one to help Harry control his new abilities when they get out of hand, using her vast knowledge of magic.
Since I haven't read it, I can't say for sure. But it's likely to feature Harry Potter, Hermione Granger, and Ron Weasley as they are the central characters in most Harry Potter - related stories. There might also be other characters like the goblins from Gringotts who would be important in a story about banking in the wizarding world.
I think Luna Lovegood would make an excellent main character in a Harry Potter Ghost Hunters fanfic. She already has a very open - minded view of the magical world and is quite in tune with the more ethereal aspects of it. Fred and George Weasley could also be main characters. Their mischievous nature would lead them to be interested in ghost hunting, and they could use their inventions to help in their investigations. Additionally, Ginny Weasley could be part of the group, being brave and having her own experiences with the supernatural at Hogwarts.
Obviously, the grandchildren of Harry Potter are main characters. They often have names that are related to the Potter family traditions. There could also be their friends at Hogwarts, who might be from different wizarding families or even Muggle - borns.
Most likely, Harry Potter would still be one of the main characters. Since it's in the Harry Potter universe, he's central to the story. He could be the one around whom the new bonds are formed or strengthened.
In addition to the ones mentioned, Dumbledore could be a main character in some fanfictions. He knew Flamel, so he could play an important role in stories about Flamel. Voldemort could also be a main character as he was after the Philosopher's Stone, and his actions could be intertwined with Flamel's story. There could also be original characters created by the fanfiction authors who interact with Flamel and the other known characters.
There could be new characters created specifically for this fanfiction that are central to the merging concept. For example, a character who has the ability to control the merged magic or someone who is the key to uniting different groups of wizards that were brought together in this fan - made story.
Ron Weasley might be another main character. His loyalty to his friends and his sometimes comical, yet brave nature could be important in a story centered around a boomslang. There could also be new characters introduced in the fanfiction that are specifically related to the boomslang, like a character who is an expert on boomslangs or has a special connection to them.
Often, the main characters are still Harry, Hermione, and Ron. But with the addition of the nanites, their personalities and abilities might change. For instance, Harry could use the nanites to better understand Voldemort's magic.
Well, Harry Potter would most likely still be a main character. His journey of growth and how he adapts to the evolving world around him would be a central focus.