One of the main themes in Naruto fanfiction is the exploration of the ninja world's politics. This could involve different clans vying for power or how the hidden villages interact. In terms of Highschool DxD fanfiction, the theme of the main character's growth not just in power but also in his relationships is popular. There are also fanfictions that focus on the mythology of the devils and angels in Highschool DxD, explaining their origins and powers in more detail than the original anime. Another theme in Naruto fanfiction could be the training of the next generation of ninjas in a different way than shown in the original.
For Naruto fanfiction, redemption arcs for villains can be a popular theme. Writers might explore how characters like Sasuke could have a different path to redemption. Another theme is time - travel, where characters go back in time to change events. In Highschool DxD fanfiction, exploring the backstories of the devil characters more deeply is a theme. Also, crossovers between Highschool DxD and other anime are becoming more popular, like a crossover with Bleach or One Piece.
One popular theme could be the relationships between the characters. For example, exploring the romantic and sometimes more intense relationships between the main character and the various female characters in the series. Another theme might be the power dynamics within those relationships, as there are different levels of power among the characters in Highschool DxD.
One popular theme is the exploration of relationships between female characters. In Yuri Highschool DxD fanfiction, writers often focus on the emotional bonds and interactions between the female characters. Another theme could be the development of unique powers or abilities within the Yuri context of the story. For example, a character might discover a new power that is related to her relationships or her own self - discovery. Also, the theme of friendship and loyalty among the female characters is quite common. They support each other through various challenges in the high school setting, which is full of supernatural elements in the Highschool DxD universe.
Power development is also a common theme. Gasper has his own set of powers, and fanfiction may delve into how he hones them. Maybe he discovers new ways to use his vampire abilities, or he trains with other characters to become stronger and more in control of his powers.
One popular theme is power - ups. In both Highschool DxD and Campione, power is a significant aspect. Fanfictions often explore characters getting new and stronger powers, and how they use them. For example, in Highschool DxD, a fanfic might focus on Issei getting a new form of his Boosted Gear.
One popular theme is the relationship development between the female characters. It could be about how they gradually fall in love, overcome obstacles in their relationship, like dealing with the opinions of other characters in the Highschool DxD world.
One common theme could be the exploration of unique power dynamics. Since Highschool DxD has a complex system of powers, in futanari fanfiction, it might show how these characters with different genders and powers interact. For example, a futanari character might have a special power that affects the relationships and battles within the story.
One popular theme is adventure. Yasaka could be on a journey to protect her territory or find a powerful relic. Another theme is friendship. She might form new alliances with other characters from the Highschool DxD universe. And of course, there's the theme of power - how she gains or uses her power in different situations.
Another popular theme is alternate relationships. The multiverse allows for different pairings between characters that might not be possible in the original story. It gives a fresh perspective on the characters' personalities and how they interact with others.
A common theme is power - up. Rias may gain new powers or improve her existing ones. This could be related to her devil heritage or through some special training or encounter.
Well, in Highschool DxD Red Claw Fanfiction, a common theme is loyalty. The characters show loyalty to their peerage leaders. For example, Kiba's unwavering loyalty to Issei. Also, the theme of redemption can be seen in some fanfictions where characters who have made mistakes in the past try to make up for it. And of course, the exploration of the supernatural world with all its different races and their cultures is also a popular theme.