What are the common themes in 'Highschool DxD OC x Massive Harem' fanfiction?

There's also 'Rising of the OC in DxD'. In this fanfiction, the OC is a reincarnated being. He uses his past - life knowledge to his advantage in the world of Highschool DxD. His harem includes characters from different factions, and the story delves into how he manages to keep them all together while facing various challenges from the supernatural world.

One common theme is self - discovery. The OC often has to figure out their place in the Highschool DxD world, especially in relation to Rossweisse. They learn about their own powers and personalities through their interactions.

One common theme is the struggle for acceptance. The disabled oc often has to face the challenges of being different in a world full of supernatural beings. Another theme could be self - discovery, as the character figures out their place in the Highschool DxD universe.

One common theme is the development of relationships. Since it's a harem - type story, the main character, usually Issei, forms different kinds of relationships with the female characters. There's often a lot of romantic tension and the exploration of how these relationships might grow over time.

One common theme is the relationship dynamics within the harem. It often involves the main character dealing with the different personalities and desires of the harem members. Another theme is the power growth of the main character, similar to the original Highschool DxD series. And of course, there's the aspect of romance and attraction among the characters in the harem.

Power is a common theme. Villain ocs often seek power in these fanfictions, whether it's magical power or influence over others. They strive to become more powerful than the main characters in the High School DxD world.

One common theme is self - discovery. The human OCs often find themselves in a new and strange world of devils and other creatures, and they have to figure out who they are in this context. For example, they might discover hidden powers or a new purpose in life.

Power struggles are common. Since vampires are often depicted as powerful beings, in Highschool DxD oc vampire fanfiction, they usually have to deal with other powerful characters. For example, they might have to face off against devils or angels.

Another theme is character relationships. Writers often explore how the characters from the two series interact with each other. This could be in terms of friendship, rivalry or even romance. For instance, Ichigo from Bleach might form an unexpected friendship with Issei from Highschool DxD.

One common theme is power - up. Just like in a game, the characters often level up or gain new abilities in these fanfictions. Another theme is strategy. They use gamer - like thinking to plan their moves against opponents in the Highschool DxD world.