It's hard to say without reading it. However, it's likely that there will be a protagonist who is either drawn into or forced into the femdom world. There could be a mentor - like female character who guides the main character through the rules and ways of this world. And there may be other characters who oppose or support the main character's journey.
The school librarian could be a main character in a femdom school story. She controls the access to books, which is a powerful position. She might have strict rules about borrowing and returning books, and if students break those rules, she has her own ways of dealing with them, like making them help with library chores for a week.
I don't know as I haven't read it, but likely the main characters would be the women in stockings who are in the femdom role.
Without having read the 'the world in 9 1 2 novel', it's impossible to accurately name the main characters. However, if we assume that the numbers 9, 1, 2 are related to the characters in some way, perhaps there are nine siblings and one of them, the firstborn (represented by 1), has a special relationship with a character who is an outcast or different in some way (represented by 2). But again, this is just wild speculation.
I don't know the main characters as I haven't read the novel.
The main characters in the '7 wonders of the world novel' could be a diverse group. There might be a young and curious protagonist, perhaps a journalist or a student, who embarks on a journey to learn more about the seven wonders. There could also be some antagonists, like treasure hunters who are willing to destroy the wonders for their own gain. And there may be local people living near the wonders who play important roles in the story, sharing their knowledge and traditions.
The main character in the Magus World novel is Lei Lin. He is a key figure in the story and drives much of the plot forward with his actions and decisions.
I don't know the main characters as I haven't read it. Maybe it has a protagonist who tries to resist the perverted nature of the world in the story.
I don't have information about the main characters in this 'refining the world novel' as I haven't read it. But they could be a young hero with great potential, an old wise mentor, or a group of friends united for the cause of refining the world.
There's also Rebecca. She is Enid's friend and they share a lot of experiences together throughout the novel.
Typically, there is a central protagonist who is the focus of the story. There may also be side characters like a wise old wizard or a brave knight.