Another way is through their role in the larger story. If there's a conflict in the fanfic, like a war between different factions, the characters can develop by taking on different responsibilities. They might start as a simple foot soldier and grow into a leader, making tough decisions and learning from their mistakes along the way.
A third storyline could be her exploration of different realms. Since it's a fanfic, the author could take her to strange and uncharted realms where she has to adapt to new cultures, learn new magic, and make friends or foes. All of this would be an exciting adventure without the focus on pregnancy.
The plot could start with the girl being left out of social events because she doesn't have a phone. Just like Cinderella was excluded from the ball at first. Then, she might meet someone who doesn't judge her by her lack of a phone. They could start a friendship or something more. Maybe she discovers a talent she has that doesn't require a phone, like painting or singing, and this talent brings her into the spotlight, similar to how Cinderella's beauty was finally noticed at the ball.
The character of Max can be developed through her internal struggles. Maybe she's attracted to the danger and freedom that the Lost Boys represent, but at the same time, she's afraid of losing her humanity. This inner conflict can drive her actions and decisions throughout the fanfic. Additionally, her physical and emotional journey, like learning to fight or dealing with the loss of a loved one, can shape her into a more complex and interesting character.
The Ghost Phoenix could be developed by giving it a unique personality. For example, it could be a very proud and noble being, with a sense of honor that guides its actions.
For Meredith, the pregnancy could be a catalyst for her to explore her maternal side more deeply. She might start to remember her own mother's experiences and draw strength from that. Deluca could grow in his understanding of Meredith's complex emotions. He would have to learn to be more patient with her mood swings and insecurities. Also, they could both develop a stronger bond as they face the physical and emotional changes that come with pregnancy.
Jacob could be developed by showing his growth in responsibility. He might start learning about things like childbirth and parenting from the human side of his world. Renesmee could be developed as she discovers new aspects of her own body and abilities during the pregnancy.
A pregnancy story could start with a mysterious event. Maybe Xena has a strange encounter with a magical being or an ancient relic that results in the pregnancy. Then Ares could initially be shocked but quickly become intrigued. He might offer his protection, but with ulterior motives. For example, he could hope that the child would grow up to be a powerful ally in his never - ending battles. Xena would be suspicious of his motives and constantly on guard.
Azirahphale's punishment could be a form of tough love. Maybe he made a hasty decision that put himself in danger, and the punishment is a way for the other characters to teach him to be more cautious. This can lead to his character evolving into a more responsible and reliable figure in the fanfic, which is a positive development for the story.
Another way is to explore her relationships. If she's a girl, she might have a different dynamic with Ash (assuming it's set in the Pokémon anime universe). Maybe she's more of a confidante to Ash, listening to his problems and offering her own cute, Pokémon - perspective advice. Also, she could interact differently with male Pokémon, perhaps showing a bit of shyness or coyness at times.
One way could be through a series of unexpected events. Maybe they are in a dangerous adventure together and in the process, some magical or strange phenomenon occurs that leads to Joey getting pregnant. For example, they come across an ancient artifact that has some sort of power over fertility.