There could also be themes related to power - ups and training. Issei, known for his growth in the High School DxD series, could be shown to learn and adapt to the magic in the Harry Potter world, and vice versa for Harry Potter characters if they are introduced to Issei's powers. This can create stories centered around self - improvement and the exploration of new powers in a different magical context.
Another theme could be crossovers in terms of character relationships. Issei might form friendships or rivalries with characters from the Harry Potter series. This could lead to interesting storylines where they have to work together or compete in magical challenges.
You can try looking on fanfiction websites such as FanFiction.net or Archive of Our Own. These platforms have a vast collection of fan - made stories. Just use the search bar and type in 'Issei Hyudou Potter' and you might find some interesting fanfictions.
Many fanfictions focus on Issei's role within the devil society. How he rises in rank, earns respect, and changes the way things are done. There are also themes related to loyalty and friendship. His relationships with his friends and comrades are often explored, showing how they support each other in the face of various challenges in the dangerous world of 'High School DxD'.
Well, the theme of sacrifice is quite prevalent. Sometimes either Issei or Rias has to sacrifice something for the other or for the greater good. Another common theme is identity. Issei, as a human - turned - supernatural being, and Rias, as a devil, both struggle with their identities at times. Their relationship helps them to better understand themselves. And the theme of destiny often comes up, as if they are fated to be together and face all these challenges as a couple.
A significant theme is also self - discovery. Being reborn gives Issei a chance to look at himself and his role in the world differently. He might question his previous actions and strive to be a better version of himself. Additionally, alternate universe scenarios are common. The fanfictions may take Issei to different settings or situations that deviate from the original plot, like a world where the power balance is completely different or where certain events didn't occur as in the original story.
One common theme is friendship development. They often start as acquaintances or even rivals and gradually become good friends. For example, in many fanfictions, they work together on a project and through that, their bond deepens.
One common theme is the growth of their relationship. It often starts from a somewhat distant or one - sided view and develops into a deep and meaningful connection. Another theme is their combined strength in battles. Writers like to show how they complement each other in fighting against enemies.
One common theme could be emotional pain. Issei might be going through heartbreak, betrayal, or loss in the fanfiction. Another theme could be physical harm, perhaps from a battle or an accident.
A common theme is power. How Issei gains power from Amaterasu or how they combine their powers. For example, in many fanfictions, Issei's combat abilities are enhanced by Amaterasu's divine energy.
One common theme is power - up. Issei often gains new powers or abilities in these fanfictions. Another theme is romance, usually involving his relationships with different female characters in the series.
Romance can also be a theme. In some issei crossover fanfictions, he might develop relationships with characters from the crossed - over world. For instance, in a crossover with a magical girl anime world, he could end up having a romantic interest in one of the magical girl characters, which then adds an extra layer of story - telling as he tries to balance his feelings with his mission or place in the new world.