Another character could be a mischievous boy. He's also in the puzzle world but instead of helping the girl at first, he tries to play tricks on her by changing the puzzles or leading her astray. But later, he might become her ally. For example, when they face a really tough common enemy or a super - difficult puzzle that requires both of their skills.
There could be a wise old man who acts as a guide for the girl. He might have been in the puzzle world for a long time and knows many of its secrets. He gives the girl hints on how to solve the more difficult puzzles.
There could be Lou, Ty's friend or colleague. She could play an important role in helping the girl adjust to the new environment, perhaps by taking her shopping for new clothes or showing her around the place. Another character could be Grandpa Jack, who gives the girl some valuable life lessons based on his own experiences.
Definitely Frodo could be one. Since he's on his important quest, the modern girl might cross paths with him. She could offer him new insights or just be an unexpected ally. Another could be Aragorn. He's a strong and noble character, and his leadership skills could be put to the test when dealing with this strange modern girl. And Legolas, the elf. His archery skills and elven wisdom could be contrasted with the modern girl's knowledge. He might be curious about her and her world.
Well, it could be about a girl who gets trapped in a world full of puzzles. Maybe she has to solve various puzzles to find her way out or to uncover some secrets. For example, she might start in a mysterious maze - like place where each turn presents a new riddle or brain - teaser. As she solves the puzzles, she could meet strange characters who either help or hinder her progress.
Maybe there's a mysterious visitor who comes to the ward from time to time. This person seems to know something about the girl's past or has some connection to her that she doesn't remember at first. As the story unfolds, this visitor becomes a key figure in the girl's life in the ward.
Without having read the 'bastards girl fanfiction', we can only guess. The main character is likely the girl who is identified as a 'bastard'. She may be accompanied by a cast of other characters. There could be a group of outcasts like her who form a kind of surrogate family. There might also be antagonists, perhaps those who uphold the social norms that marginalize her. And then there could be characters who are initially indifferent to her but later become important in her journey, like a kind - hearted noble who starts to see her worth beyond her 'bastard' status.
Obviously, Fireheart as a girl would be the main character. She would be the center of the story, with her actions and decisions driving the plot forward.
Well, the blueberry girl herself is obviously a main character. She's usually the center of the story with her unique traits. There might also be a sidekick, like a little talking animal that accompanies her on her adventures.
Since it's named 'the sunlight girl fanfiction', the girl herself is bound to be a main character. There could also be other characters like her friends or family members who support her or are part of her journey. Maybe there's an antagonist as well, someone who is opposed to her because of her sunlight - like qualities, perhaps someone representing darkness or jealousy.
Obviously, Kaneki as a girl would be one of the main characters. Depending on the plot, other characters from the original story like Touka might also play important roles. They could have different relationships with Kaneki now that she's a girl. For instance, their friendship or rivalry might change in unexpected ways.
It could be that she didn't like the story or the art style and decided to break it apart in a fit of anger. Or perhaps it was an accident and not intentional at all.