I don't know as I haven't read the book.
I haven't read it yet, so I'm not sure about the main plot.
The main characters are the seven members of the Secret 7 club.
There might be a female lead who is at the center of the secrets. For example, she could be a woman with a past she is trying to hide, and her actions and relationships are shaped by this need to keep things in secret.
The two main characters in 'Secret Window, Secret Garden' are Mort Rainey and John Shooter. Mort Rainey is a writer living his life when suddenly he is faced with this strange situation. John Shooter, who appears out of nowhere, is the catalyst for all the chaos in Mort's life. Mort is the character we follow through his psychological journey as he tries to figure out what's going on with Shooter's claims. Shooter is the mysterious and somewhat threatening figure that forces Mort to re - evaluate his own work and sanity.
Typically, there is the mother of the secret baby. She is a central figure as she holds the secret and has to deal with the consequences. There is also often a father figure, who may or may not be aware of the baby at first.
I don't know specifically as I haven't read it. But they could be ordinary people who get drawn into the secret world, like a young adventurer or a curious scientist.
I don't know as I haven't read the book. Maybe it has characters like a young adventurer who stumbles upon the secret.
Since I haven't read it, I can't say for sure. But likely the sisters would be main characters, perhaps their parents or other family members could also be important characters in the story.
The main characters in secret rooms novel can vary greatly. One might be a family member who has just inherited an old mansion with secret rooms. They are determined to find out what's in those rooms, maybe to uncover family secrets. Another could be an archaeologist - type character who is interested in the historical significance of the secret rooms and the artifacts they might contain.
I'm not sure specifically as we don't have much information about this'secret scripture novel'. But typically, there could be a protagonist who is on a quest to understand or protect the secret scripture. There might also be an antagonist who wants to use the scripture for their own evil purposes.