Obviously, the orphan boy is the central character. Additionally, there might be a strict but fair orphanage caretaker. And there could be a wealthy benefactor who takes an interest in the boy's future and tries to help him in different ways.
Not having read 'the orphan boy story', it's hard to say for sure. However, the orphan boy himself is the central character. There could be other orphans in the story who become his friends or rivals. There may also be an adult figure, like a teacher or a priest, who plays an important role in the boy's life, either by guiding him or by providing some form of support or challenge.
Another character could be a villain who is hunting down any remaining Targaryens. He sees the orphan boy as a potential threat because he might grow up to claim power. This villain adds conflict and danger to the story, forcing the orphan boy and his newfound friends to constantly be on the run and develop strategies to outwit him.
Since we don't know the details of 'the dream of an orphan boy story', it's difficult to name all the main characters. However, the orphan boy is the obvious main character. There could be an antagonist as well, perhaps someone who tries to stop the boy from achieving his dream. It could be a bully in the orphanage or someone in the outside world who discriminates against him because he is an orphan. There might also be a mentor - like an old man who gives the boy advice and helps him on his path.
Obviously Jerry is one of the main characters since it's his story. There might also be other orphans in the orphanage who play important roles, like his best friend there.
The main characters are, as the title suggests, the orphan boy and the elk dog. The orphan boy is likely a central figure who experiences a journey or some kind of transformation. And the elk dog, which is probably not an ordinary dog but has some special qualities that play an important role in the story.
The main characters are obviously the orphan boy and the elk dog.
Perhaps there's an antagonist, like a person from the orphanage who has some ulterior motives. Maybe this person doesn't want Bones to adopt the boy because they have other plans for the child. But Bones has to fight against this person to keep the boy.
There might be a wizard or a magical creature who causes the transformation. This character would play a significant role as they are the catalyst for the whole story. For instance, if it's a fairy, she might have her own motives for turning the boy into a bride, like teaching him a lesson about vanity or pride.
There could also be other secondary characters. For instance, the boy's parents who hire the cockvore babysitter. They might be clueless about the true nature of the cockvore. And then there could be neighbors or friends of the boy who notice something strange about the babysitter, which could add some conflict or mystery to the story.
The main characters could be the country boy himself, of course. And a girl from the same small town, like the local baker's daughter or the farmer's niece. They might have known each other since childhood.