Jacob could also be a major character. He may have a different reaction to Bella as a geisha compared to Edward. Maybe he sees her new identity as something that distances her from him and his werewolf pack, or perhaps he is attracted to her in this new form in a different way.
The other Cullens, like Alice, could play important roles. Alice, with her ability to see the future, might have some premonitions about how Bella's geisha status will affect the family and their relationships in Forks. She could be either supportive or worried about the changes Bella brings.
Edward would definitely be one of the main characters. His relationship with Bella, now a geisha, would be very interesting to explore. He might be both intrigued and a bit confused by this new side of her.
It might be that Bella, as a geisha, has a unique allure that attracts both Edward and Jacob in different ways. Her geisha training could give her an edge in understanding the hidden emotions and power dynamics among the characters in Twilight. For example, she could use her skills of perception and charm to deal with the Cullens' secrets and the Quileute tribe's traditions.
A doctor named Dr. Smith could be a main character. He could be a strict but fair physician who at first doubts Bella's abilities but later comes to respect her.
Alice could be a main character. Since she can see the future, she might sense something special about the new coven and be the first to approach them with Bella. Her insights could be crucial in understanding the new coven's intentions.
There could be her drill sergeant, a tough but fair person who helps shape Bella into a proper navy personnel.
Her parents might be important characters. They could either be supportive of her career choice or initially be against it, thinking it's too difficult. Also, there could be a senior lawyer at the firm where she interns, who takes her under his or her wing and guides her through the complex world of law.
A gruff but kind - hearted ranch hand named Jake could be a main character. He's been on the ranch for years and knows all its secrets. He initially sees Bella as an outsider but gradually warms up to her and becomes her mentor in ranch - related things.
There could be a dance instructor. Maybe someone who notices Bella's potential even though she's trying to keep her dancing a secret. This instructor could play a key role in her journey as a dancer.
Another possible main character could be the base commander. Let's say Commander Smith, who notices Bella's potential and gives her special tasks or opportunities, which then drives the story forward as Bella has to prove herself worthy of these tasks.
There could be a female character, Sofia, who is another member of the mafia. She sees Bella as a threat at first, thinking she'll steal her position or the attention of the men in the mafia. But as time goes on, they might form an unlikely alliance. There may also be a young and ambitious mafia underling named Antonio, who is always looking for ways to climb the ranks and his actions often impact Bella's situation in the story.
There could be Edward. Even if Bella is now immortal, Edward might still play a significant role. He could be either her eternal love or her adversary depending on how the fanfiction is written. Another character could be Alice. Since Alice has her own special abilities, she might be there to help Bella navigate the new world of immortality. For example, she could foresee some of the challenges that Bella will face. Also, Jacob might be a main character. His relationship with Bella, whether it's a friendship or something more complicated, could be further explored in the context of Bella's immortality.