One way is to explore her family background more. For example, showing how her upbringing in the devil society influenced her leadership style in the student council.
Sona could be developed further by giving her new challenges related to her powers. Like she discovers a new aspect of her devil abilities but has to learn to control it quickly to face an emerging threat.
One possible fanfiction could be about Rias and Sona teaming up for a school event. They might put aside their usual competitiveness and work together to organize a devil - related festival at the school. They could combine their unique skills and powers to create an amazing event that not only impresses the other students but also strengthens their bond as friends.
At first, Naruto might be a bit confused by Sona's world, but his natural curiosity would drive him to learn more. He would ask her a lot of questions, and Sona would find his naivete endearing yet also frustrating at times. As they spend more time together, Naruto would start to understand Sona's motives better and would do his best to support her. He might even start to develop a special bond with her, like a really good friendship or something more, depending on how the fanfic develops.
First, think about their backstory. For example, if they are a devil, what made them become one? Maybe they had a difficult family situation in the devil world. Second, give them unique abilities that fit within the High School DxD universe. It could be a special type of magic or a physical ability like super speed. Also, consider their personality. Are they shy, bold, or mischievous? And finally, think about their relationships. How do they interact with Sona? Do they admire her, or are they rivals? All these elements combined will make a believable character.
One possibility could be that Sona's brother is a powerful figure in the underworld. He might be involved in political intrigue within the devil society. For example, he could be trying to form alliances with other noble devil families to increase the power and influence of Sona's family. Maybe he has some special abilities that are yet to be discovered by others, which he uses to his advantage in the complex power dynamics of the Highschool DxD world.
A fanfiction could show how Rias and Sona first became friends. Maybe it was during a difficult time at school when they both had to face some sort of discrimination from other devils because of their different leadership styles. They found comfort in each other and decided to support one another from that moment on.
One way to develop her character is to have her learn new skills. For instance, she could start training in martial arts or some form of magic that is accessible to humans in the Highschool DxD world. As she learns, she could face setbacks and challenges that force her to grow both as a fighter and as a person.
Tiamat could be developed further by exploring her relationships with other characters. For instance, if she starts to mentor a young character, it would show a different side of her. She could teach them about her powers and the history of her kind.
Start with small interactions. For example, have them meet in the school library while looking for books on magic. This initial encounter can be the foundation for their relationship.
Explore their differences and how they deal with them. Sona is a devil with her own set of values and powers. The OC could be from a different background, maybe a human with some latent supernatural abilities. Their different perspectives can cause friction at first but as they learn to understand each other, it can turn into mutual respect and love. For instance, Sona might be used to a more hierarchical way of doing things in the devil world, while the OC might have a more egalitarian view. By working through these differences, their relationship can develop in an interesting way.
Yes, there are quite a few. You can find them on various fanfiction websites. Some focus on their relationship developing gradually as they face different challenges together in the Highschool DxD universe.