Voldemort would remain a major character. Harry's new abilities and perspective from being raised by Death would make their conflict even more complex. Harry might approach the fight against Voldemort with a different strategy, one that is influenced by the teachings of Death.
Obviously, Harry Potter himself would be a main character. Elrond, who is raising Harry, would also be a central figure. There might also be other elves like Arwen, Elrond's daughter, who could play important roles. Maybe some of Harry's friends from Hogwarts could make appearances in the story, even if it's just in his memories.
Obviously, Harry Potter himself would be a main character. Then, there would probably be some important goblin characters who raise him. For example, a wise old goblin who acts as his mentor, teaching him everything from magic to the ways of the goblin society.
Well, Harry Potter is the central figure, but the Weasley siblings are key too. Fred and George could be like his fun - loving older brothers, teaching him all kinds of mischievous spells and pranks. Ginny would be like a sister, and their relationship could develop in a really interesting way. And Percy, despite his differences from the rest of the family, would also be an important character as Harry would be part of the family dynamic that Percy is also a part of.
There could be an antagonist in the fanfic. Maybe someone who had a vendetta against Harry Merchant and was somehow involved in his death. This character would add conflict to the story as the people left behind try to figure out what really happened to Harry.
Well, depending on what 'rq' stands for, it could be a group of original characters created for the fanfiction. Maybe there's a wise old wizard who takes Harry under his wing as part of this 'rq' upbringing.
Obviously, Harry Potter would be the main character since it's in his name. He is the one who befriends Death. Hermione Granger and Ron Weasley are also likely to be important characters. They are Harry's closest friends and would be involved in the story, either trying to understand Harry's new friendship with Death or being affected by it in some way. For example, they might be worried about Harry's sanity or the implications of befriending such an otherworldly being.
Obviously, Harry Potter himself. He's the one who has become the Master of Death. Hermione and Ron would also be important. They'd be there to support Harry, and also to question his new power and the moral implications. Dumbledore might also play a role, perhaps as a guide from beyond the grave, since he was always so interested in the Deathly Hallows and what it means to be the Master of Death.
Obviously, Harry Potter and the Mad Hatter. But there could also be other characters from the Harry Potter universe making appearances. Maybe Dumbledore would come to check on Harry and be completely bewildered by the Mad Hatter's ways. And of course, there could be some of the Wonderland characters popping up too, like the March Hare or the Cheshire Cat, adding more chaos to Harry's life.
The main characters in 'Harry Potter raised by Winchesters' fanfiction would have some interesting interactions. Harry would surely have a lot of interaction with the Winchesters' enemies as well. Demons and other supernatural beings that the Winchesters fight would see Harry as a new target or a strange addition to the mix. In the wizarding world, Harry might interact with Snape in a more confrontational way, as his upbringing by the Winchesters could make him less patient with Snape's attitude. Also, new characters from the cross - over of the two universes could be created, and Harry would be at the center of those interactions.
Obviously, Harry Potter himself would be a main character. And the Weeping Angels would play a huge role too, acting as his guardians or captors depending on how the story is written. There might also be some Hogwarts professors who try to rescue Harry or understand his situation.