Well, one possibility is that Bella's presence changes the dynamic between Klaus and Elijah. They might start to see things from a different perspective because of her. For example, Klaus, who is often seen as the more volatile one, could become more protective of Bella, which in turn makes Elijah more accepting of Klaus's actions. And Bella might introduce them to new ideas or values from her own human experience.
A potential storyline could be that Bella discovers a hidden power within herself while living with them, and Klaus and Elijah have to protect her from other supernatural beings who are interested in her new - found power.
One possibility is that Klaus would try to claim the baby as his own, regardless of who the father really was. He's a possessive character, and having a child with Bella could be a way for him to have more power or control. Marcel, on the other hand, might be more concerned about Bella's well - being.
She could change the whole dynamic of Elijah's life. For instance, if Elijah was on a path of revenge in his original timeline, Bella might be able to show him a different way. She could introduce him to new ideas and values that were not present in his time. This could lead to a completely different version of Elijah, one who is more open - minded and less consumed by his past grudges.
It could also focus on their personal growth within the marriage. Bella might have always been a bit shy and Elijah helps her come out of her shell. He encourages her to pursue her dreams, like starting her own small business. In turn, Bella helps Elijah become more in touch with his emotions and they both become better versions of themselves through their relationship.
Well, the plot could start with Bella stumbling upon Klaus in a situation where she realizes he's not just the big bad everyone makes him out to be. Maybe she helps him in some way, like hiding him from his enemies, and from there, a friendship begins.
One possible plot could be that Bella and Elijah face challenges from the vampire and werewolf communities. Their relationship might be seen as an oddity or a threat. For example, other vampires could be jealous of Elijah's relationship with Bella, or werewolves might see Bella as a target because of her connection to a powerful vampire like Elijah.
Well, it could involve Bella discovering her true heritage as Elijah's daughter. Maybe there are conflicts with other characters who have different intentions regarding her. For example, some might want to use her for power, while she just wants a normal life.
One great Klaus and Elijah fanfiction could be 'The Bond Beyond Blood'. It delves deep into their complex relationship, exploring how their loyalty to each other is tested in a world full of supernatural threats. Another is 'Klaus and Elijah: Brothers in the Shadows' which focuses on their early days and how they came to be the powerful beings they are. There's also 'Elijah's Redemption through Klaus' that shows how Elijah's actions are often influenced by his love and concern for Klaus.
Another theme is loyalty and betrayal. Given their complex relationships and the world they live in, there are often situations where loyalty is tested. For example, Elijah's loyalty to Klaus might be put to the test because of his feelings for Elena. And vice versa, Klaus might feel betrayed if Elijah gets too close to Elena.
One interesting Klaus and Elijah fanfiction could be about their early days as vampires. It might explore how they dealt with the newfound powers and the moral dilemmas that came with it. For example, a story could show Elijah trying to keep Klaus in check during his more violent outbursts.