It could start from a moment of mutual rescue. For example, Hayley saves Rebekah from a dangerous vampire hunter, and in return, Rebekah helps Hayley when she's in trouble with her werewolf pack. This mutual indebtedness gradually turns into something more, and they realize they have deeper feelings for each other. They start to spend more time together, and before they know it, they're falling in love and decide to get married.
In the fanfiction, their relationship might begin with a simple friendship. They meet at a neutral place in the supernatural world, like a market where all species gather. They start chatting, find they have common interests, like a love for art or music that exists in their world. As they continue to meet and talk, their friendship blossoms into love, and eventually, they take the step of getting married.
Perhaps it starts with an unexpected alliance. They might be forced to work together against a common enemy, like a powerful witch or an ancient vampire. During this time, they start to see the good in each other. Rebekah might admire Hayley's tenacity and Hayley could be intrigued by Rebekah's charm.
Well, their life could be filled with a lot of supernatural drama. They'd probably have to deal with the politics of the supernatural world together. Maybe they'd be really protective of each other. For example, Rebekah with her vampire strength and Hayley with her werewolf abilities would make a formidable team against any threats. And they'd also have to navigate their relationships with other characters in the fanfiction universe.
It could also change the social norms within the vampire community. Their relationship might inspire other vampires to look beyond traditional family rivalries and form new relationships. This could lead to more mixed - blood vampire families in the long run. Moreover, they could use their combined influence to enforce new rules or change existing ones in the vampire world, like how vampires interact with humans or with each other in different territories.
Rebekah and Marcel's relationship would change in many ways. With the pregnancy, they would become more protective of each other. Marcel might become more possessive, not wanting Rebekah to be in any danger. Rebekah, in turn, would rely on Marcel's strength. They would also have to communicate more about their future and the future of their child. There could be some disagreements as well, for example, about where to raise the baby or how to handle the baby's potential powers if it has any. But overall, their relationship would grow stronger as they face these new challenges together.
Family is also a big theme. As they are part of a complex supernatural family, the fanfictions might explore how their marriage affects the family dynamics. They could be trying to protect their family together or dealing with family members who don't approve of their union. In some stories, they might also be thinking about starting their own family, which adds another layer of depth to the plot. Another common theme is power. Given their positions in the supernatural world, their marriage could change the balance of power, and fanfictions often play around with this idea.
Their relationship could develop through shared challenges. For example, they might face a new and powerful enemy in a game. Working together to defeat it would bring them closer. Kirito's leadership and Sinon's precision would be crucial.
Their relationship could start from mutual respect. They've been comrades for a long time. As the story progresses, Natsu might realize his deeper feelings for Erza during a particularly dangerous mission where he almost loses her. This realization could lead to him confessing his love, and from there, their relationship would develop into a romantic one and eventually marriage.
The relationship could develop through shared experiences. Maybe they have to face a new common enemy together. This would force them to rely on each other, and in the process, they start to respect each other's skills. Harry's courage and Voldemort's strategic mind could work well together in combat. As they spend more time together, feelings other than hatred might start to emerge, like a strange form of friendship or even more complex emotions.
In fanfiction, their relationship development often involves facing external threats together. When they are married, they become a united front against new evils. This makes them rely on each other more, strengthening their bond. Also, they start to share their innermost feelings and secrets, which deepens their relationship on an emotional level. For instance, Spike might share his past traumas with Buffy, and she in turn might open up about her fears as a slayer.
Maybe it started with mutual admiration. The student might have been attracted to the teacher's knowledge and charisma, and the teacher could have seen something special in the student.
Maybe you were a medic - ninja who treated Naruto after a particularly tough battle. He was so impressed by your skills and your kind heart that he started to visit you more often. You'd share stories about your lives, and gradually the relationship would turn into something more romantic. You'd start going on walks together around the village, and before you knew it, you were in love and thinking about marriage.