I'm not sure who the main characters are as I haven't read the novel. But they could be people who are at the forefront of the worldshift, like a young adventurer or a wise old leader.
The main theme could be about new beginnings. It might explore how characters face changes in their world and start anew, perhaps dealing with challenges and opportunities that come with this shift.
There could be a young adventurer as a main character. This person is tired of their ordinary life and decides to start anew by exploring the unknown world. They are brave and full of curiosity, ready to face whatever comes their way in this new beginning.
Kratos is surely one of the main characters as he is the central figure in the God of War series.
It's hard to say without reading it. It could be the original characters like Harry, Hermione, and Ron if it's a continuation of their story. Or it might focus on new characters created by the fanfic author.
There might be an antagonist as well. This character could be causing problems for the main character throughout the story, starting from the beginning and being a source of conflict until the end. For example, a villain who is trying to stop the protagonist from achieving their goals.
Without having read 'In the Beginning Graphic Novel', it's hard to say exactly. However, often in graphic novels, there are protagonists who face challenges and antagonists who create obstacles for them. Maybe there's a young protagonist in this one, trying to discover something about themselves or their world.
I'm not entirely sure as I haven't read the specific 'the beginning of everything novel'. But usually, there's a protagonist who drives the story forward. There might also be a sidekick or a mentor figure who helps the main character along the way.
There could be the children of the original characters. For example, Harry Potter's son or Hermione Granger's daughter might be main characters.
Harry Potter himself is likely to still be a main character. He's the face of the series. Hermione and Ron will probably also be important. But new characters might be introduced too, perhaps a mysterious new student or a powerful wizard from a far - off land.
It could be a young adult who has just graduated from college and is starting their first job, so they are beginning a new path. The 'lemon' could be their quirky roommate who makes their new living situation interesting.