I don't know as we haven't been given any details about the story. It could be the neighbors themselves, like an old lady and a young family.
There's the inquisitive protagonist who drives the story forward by being interested in the neighbor's secrets. The neighbor is a very important character as well. His actions and the secrets he holds are what the whole story is about. There might also be some minor characters like other neighbors who could potentially play a role in the background, but the focus is mainly on the protagonist and the mysterious neighbor.
The main character is the curious person who wants to explore the neighbor's house. And of course, the neighbor himself is also a very important character.
The boy is surely one of the main characters as he is the one being spanked. And the neighbor must also be important. Maybe the neighbor is the one who tells the story, or the neighbor has some sort of influence on what happens to the boy, like if the neighbor complains to the boy's parents about his behavior which then leads to the spanking.
In the 'hello neighbor real story', the most important characters are the player character and the titular neighbor. The player is driven by curiosity to explore the neighbor's house. The neighbor, on the other hand, is a rather mysterious figure. He seems to be hiding something big, and he defends his house against the player's attempts to infiltrate. There are no other really prominent characters in the basic story of the game.
Since I don't know the exact story, I can't say for sure. But it could be the family members like the parents, kids, and maybe an interesting neighbor.
The main characters are the player, who is the inquisitive one trying to discover the neighbor's secrets, and the neighbor himself, who is mysterious and guards his house vigilantly.
I don't know for sure as I haven't read it. But it could have a neighbor as the main character, maybe someone who is kind - hearted and always ready to help others in the neighborhood.
Since I don't know the exact 'the new neighbor novel', I can't say for sure. But likely, the new neighbor would be one of the main characters. There might also be a character from the existing neighborhood who becomes closely involved with the new neighbor, like a curious neighbor or someone who has an instant connection with the new arrival.
The main characters in 'a good neighbor novel' could be a variety of people. There might be a friendly neighbor who is always there to lend a helping hand, perhaps a single father who is trying to raise his kids while also being a good neighbor. And there could be a nosy neighbor who always seems to be in everyone's business, which creates some interesting plotlines. Maybe there's also a reclusive neighbor who the others slowly get to know throughout the story.
I don't know as I haven't read the book. But typically, there would be the new neighbor as one of the main characters. And probably some of the people from the neighborhood who interact with the new neighbor.