The main characters would be Bella and Jacob at the core. Bella as the pregnant one has to face many challenges. Jacob, by leaving, creates the main conflict. Additionally, the baby itself could be considered a sort of character in a way. It could have an influence on Bella's decisions and actions. And characters from the werewolf pack or the vampire coven might also make appearances, depending on how the fanfiction is written.
Bella is surely a main character. Since she's pregnant, her journey of dealing with the pregnancy, her emotions, and her future plans are key. Jacob, despite leaving, will still be important as his departure sets the story in motion. There may also be other characters like Bella's family or friends from the Twilight series, such as Charlie or Alice. They could be involved in Bella's life during this time, providing support or causing additional drama.
There could also be new characters introduced in the fanfiction. Maybe a doctor who specializes in the unique situation of a human - werewolf pregnancy, or a friend who has been through a similar experience and can offer advice to Jacob and Bella. But overall, Jacob and Bella remain at the heart of the story.
Bella herself could also be a significant character in this fanfiction. Her relationship with Jacob and her sister would be crucial. Her reactions to any potential relationship between Jacob and her sister could drive the story forward. Also, other characters from the Twilight series like Edward might make appearances, especially if they are involved in the overarching story related to Bella.
Obviously, Bella is one of the main characters. Since she is the one who is pregnant. The wolves would also be main characters. There could be a particular wolf who has a special connection with Bella, like a love interest or a very close friend.
There could also be other characters from the Twilight series involved. For example, the members of Jacob's wolf pack might play a role. They could be trying to mediate between Jacob and Bella, or they might side with Jacob, adding more tension to the story.
Another character that could be involved is Charlie, Bella's father. His reaction to his daughter being pregnant in the strange world of Eclipse could be a significant part of the story. He might be confused, worried, or try to protect Bella in his own way. Also, some of the werewolf pack members aside from Jacob could also make appearances and contribute to the story based on their relationships with the vampires and Bella.
One interesting aspect could be how Bella copes with being pregnant alone after Jacob leaves. Maybe she leans on her other friends in the story for support. Another could be the reaction of the werewolf pack to the situation, whether they choose to help Bella or not.
Charlie, Bella's father, would probably be a significant supporting character. He might be initially shocked but then come around to support Bella and Jacob in raising the baby. The wolf pack could also be important. They might offer their protection and guidance to Jacob as he becomes a father.
Sure. There might be some new characters created specifically for this fanfiction. Maybe a wise elder in the werewolf community who gives advice to Jacob about how to handle the situation with Bella and the pregnancy. Or perhaps a human friend of Bella's who discovers the truth and has to deal with the shock of the supernatural world.
Bella, obviously. She is the one who is pregnant and will have to face all the physical and emotional changes that come with it. Her life will be completely turned around as she prepares to be a mother.
Alice could be a supporting character. She might have visions about Bella's pregnancy and the future of the baby. Jacob could also be involved, perhaps initially being angry or concerned about Bella's situation with Aro. Carlisle could be another one, as his medical knowledge as a vampire doctor could be useful in dealing with Bella's pregnancy.