What are some interesting plot ideas in Highschool DxD His Angel Fanfiction?

One plot idea could be Shirou Emiya, as an angel, arriving at the Highschool DxD world and getting involved in the ongoing power struggles. He might use his skills from the Fate series to help out the various factions while also trying to maintain his angelic identity.

A good plot for Highschool DxD fallen angel OC fanfiction could start with the OC being hunted by a group of vengeful angels. As they run, they end up in the territory of the devils and have to make a deal with them to survive. Along the way, they fall in love with a devil, which creates a whole new set of problems as their two worlds collide. Or, the OC could be trying to solve a mystery that dates back to the very beginning of their fall, something that involves a prophecy that only they can fulfill.

A plot could also focus on a new character who is a hybrid of the two universes. They have the powers of both a devil from High School DxD and a wizard from Harry Potter. They struggle to find their place in either world as they are too different from the norm in both, and they embark on a journey to create their own identity and purpose.

One idea could be exploring new power-ups for the characters. For example, Issei could discover a hidden ability within his Boosted Gear that allows him to time - travel briefly during battles, adding a new strategic element. Another could be focusing on the relationships in the future. Maybe Rias and Issei have a family and the story could revolve around their children's upbringing in the supernatural world.

One idea could be a new character joining the school who has a unique supernatural ability that no one has seen before. This could disrupt the existing power dynamics and create all sorts of interesting interactions and challenges.

One idea could be to have a new character enter the world of Highschool DxD who challenges the existing power hierarchy and calls out the flaws in the main characters' actions. For example, this new character might see Issei's pervy ways as not just a comical trait but something that is disrespectful to the female characters and start a movement to change the way things are done in the school.

Well, perhaps a fanfiction where Griselda gets transported to a different dimension. In this new place, she has to adapt quickly and find a way back home. Along the way, she meets new allies and enemies. This would be a great way to explore her character in a different setting.

One idea could be a succubus character trying to resist her natural instincts in the high school setting of Highschool DxD. For example, she might struggle with not using her powers to manipulate the male characters around her.

One idea could be a new character joining the school who has a mysterious power that both the devils and angels are interested in. This new character could disrupt the existing power balance in the school.

One plot idea could be Tiamat adjusting to the modern world in the Highschool DxD universe. Maybe she has to deal with the different social norms and the unique magic systems there.