One idea could be creating an OC who is a master hacker. In the chaos of the 'Highschool of the Dead' world, this OC could use their skills to hack into security systems, gather information about the zombie hordes or even try to find a possible cure. For example, they might hack into a military base's communication system to see if there are any rescue operations planned.
You could write about an OC who is a half - angel, half - devil. Their internal struggle between the two natures and how they fit into the world of Highschool Dxd, trying to find their place among the devils, angels and fallen angels. It could explore themes of identity and acceptance.
An interesting OC for a Highschool DxD fanfiction could be a half - angel, half - devil. Their internal struggle between the two natures would make for a great character arc. They could be trying to find their place in the world where angels and devils have their own agendas, and they don't fully belong to either side.
One idea could be a crossover where Naruto characters are suddenly thrown into the Highschool of the Dead world. They could use their ninja skills to fight off the zombies. For example, Naruto could use his shadow clones to distract the zombies while others find a safe place. Another plot could involve a Highschool of the Dead character getting ninjutsu powers and having to learn to control them like a Naruto character. Maybe they accidentally use a fire - style jutsu in the middle of the school, causing chaos among the survivors and the zombies.
One idea could be to explore the backstories of the minor characters in more depth. For example, the story could focus on a side character's journey before the zombie apocalypse and how they've changed since then. Another plot could be a survival story that takes place in a different location than the original, like an isolated island where they have to deal with not only zombies but also limited resources.
Well, you could create an OC that has the power of prophecy. This OC in the 'Highschool DxD' fanfiction would know about future events and could either try to prevent disasters or manipulate them to their advantage. Maybe the OC is a godlike figure who comes from a different dimension where the rules of power are much different. They introduce new forms of magic or combat techniques that the characters in Highschool DxD have never seen before.
One idea could be creating an OC who has a unique power related to time manipulation. This OC could use their power to turn back time during battles in the 'Highschool DxD' universe, catching opponents off - guard. Another idea is an OC with a power based on sound. They could use sonic waves for offense and defense, like creating a sonic shield or a powerful sonic blast.
One idea could be creating an OC who is a half - angel, half - devil hybrid. This would bring a unique dynamic as they struggle with the opposing natures within them. They could have special powers that are a combination of angelic and devilish abilities, like the power to heal but also to curse. Another idea is an OC from a different mythological background, such as a Norse or Egyptian origin, who gets involved in the Highschool DxD world. This would introduce new elements and cultures into the story.
One idea could be a dragon OC that has the ability to transform into different elemental forms. For example, it can be a fire - breathing dragon in combat situations, but a water - based dragon for healing or stealth purposes. This would add an interesting dynamic to the story as it could befriend different characters based on its form.
Another interesting concept is an SI OC who is a transfer student from a different supernatural realm. They bring with them their own set of customs and powers that are completely new to the characters in Highschool DxD. This could lead to some really fun cultural clashes and power exchanges.
One interesting plot idea could be a pre - apocalypse story within the Highschool of the Dead universe. Maybe showing how the relationships between the main characters were developing before the zombies showed up. For example, Rei and Takashi's friendship turning into something more complex as they dealt with normal high school drama.