In this fanfiction, Edward might be one of the mates as he was so central to Bella's story in the original. Jacob could also be there due to their history. Additionally, there could be a character who is neither vampire nor werewolf but has some other supernatural power, like a psychic who can see the future. This psychic might be drawn to Bella because they sense she is a key figure in some upcoming event and forms a strong bond with her as a mate.
Perhaps one of the mates is a fellow student at Bella's school. He could be a smart and kind human boy. And the other mate could be an otherworldly being, like a faerie with magical powers. This would create a really interesting dynamic as Bella tries to navigate relationships with such different individuals.
One of the mates could be a mysterious and brooding vampire. He has a dark past but is drawn to Bella's innocence and kindness. The other mate might be a werewolf, strong and protective, who has known Bella for a long time and has always had a soft spot for her.
In the fanfiction, perhaps Bella's multiple mates are from different supernatural groups. This could bring about a unique dynamic where she has to balance the needs and cultures of each group. Maybe she uses her relationships to bridge the gap between the vampires and werewolves, leading to a new era of peace in their world. It could also mean that she has to deal with different forms of affection, like the cold yet passionate love of a vampire mate and the warm, instinctual love of a werewolf mate.
It could be a new character entirely. Maybe a hybrid of some sort, half - vampire and half - werewolf, which would be a very unique and interesting choice for her true mate. This would bring a whole new set of dynamics to the story as Bella has only been involved with either vampires or werewolves before.
One possibility could be that Bella is in a world where having multiple mates is common. She might struggle to balance her feelings for both mates. Maybe one mate is more adventurous and the other is more nurturing, and she has to figure out how to incorporate both relationships into her life.
There could be characters from the original stories that Bella and Jane come from. For Bella, characters like Edward or Jacob might still play a role, perhaps in the form of her past relationships that now create some sort of complication in her new relationship with Jane. From Jane's side, other Volturi members could be involved, like Aro or Caius, who might have opinions on Jane's new mate.
It could be a werewolf. In the Twilight universe, werewolves and vampires often have a complex relationship with humans. A werewolf might have been Bella's real mate, perhaps one that she met briefly before Edward entered the picture. Maybe this werewolf had a special connection with Bella that was disrupted when Edward came along.
In this 'bella has two mates fanfiction', perhaps the two mates are from different factions or species. This creates a lot of conflict and intrigue. Bella may find herself in the middle of a power struggle or a cultural clash. She could be trying to bridge the gap between the two, while also dealing with her own romantic feelings. The story could explore themes of acceptance, love across boundaries, and the power of unity.
A vampire from an ancient and powerful coven. Maybe a vampire who has been in hiding for centuries and emerges when he senses Bella. His different values and way of life compared to Edward would make for an exciting story.
Maybe it's Loki. Loki is known for his mischief and cunning. His complex personality would add a lot of drama to the relationship with Bella. He could bring a whole new level of chaos to the Twilight universe.