Asia Argento would be a really interesting character to pair with the SI. Her kind and gentle nature combined with her healing abilities could be a great match for the SI's more strategic and power - seeking mindset. The SI could help her gain more confidence in using her powers, perhaps by treating her abilities like they would in a game upgrade system. Xenovia could also be a good match. Her determination and combat skills could interact well with the SI's gamer - influenced fighting style.
Rias Gremory would be a popular choice. She's a strong and important character in the Highschool DxD world. Her leadership and power could be a great contrast or complement to the SI's gamer - like abilities. Another could be Akeno Himejima. Her mysterious nature and powerful attacks could create interesting interactions with the SI. The SI could help her unlock new abilities using their gamer knowledge.
Akeno can be a popular character as well. Her mysterious nature and powerful abilities make her an interesting character to interact with the SI. She might be part of the SI's adventures, either as an ally or an unexpected challenge.
Issei Hyoudou can also be a popular character in these fanfictions. His growth from a normal human to a powerful devil is an interesting arc. In Si Sitri fanfiction, he could interact with the Sitri family in various ways, perhaps getting involved in their schemes or forming relationships with the Sitri characters.
One interesting plotline could be the main character using their gaming knowledge to gain unique abilities in the Highschool DxD world. For example, they might apply strategic thinking from games to outwit opponents in battles.
One idea could be the SI (Self - Insert) character using their gamer knowledge to unlock unique powers in the Highschool DxD universe. For example, they might figure out a way to level - up their devil or angel abilities like in a game. Another plot could involve the SI character forming a special team with the existing characters in the series to compete in some sort of supernatural gaming tournament within the DxD world. This could bring in new challenges and alliances.
The adaptation of gaming mechanics into the Highschool DxD world is also really cool. The SI OC might introduce things like RPG - style leveling systems for the characters in the story. So instead of just the normal power - ups in the original series, characters could gain experience points and level up, unlocking new skills and abilities, which would change the power dynamics and the overall flow of the story.
There are fanfictions where the Si (self - insert) character changes the plot significantly. They might form different alliances or find new ways to deal with the challenges in the Dxd world. This could lead to really interesting storylines that deviate from the original plot in exciting ways.
There's an OC named Alex who is often popular. He has the power to control time on a small scale, which is a really cool ability in the Highschool DxD universe. Another is Sophia, who is a half - angel half - devil OC with the ability to nullify any demonic or angelic power. She is often written as a very complex character, trying to find her place in a world that doesn't fully accept her mixed heritage.
It could be a rogue fallen angel who is jealous of the godlike SI's power. This fallen angel might see the SI as a threat to their own plans of ruling the underworld or causing chaos between the three factions in the High School DxD world.
Well, clearly the self - insert (SI) character and Serafal are main characters. The SI is often the protagonist through whose eyes we view the story. Serafal, being a significant figure in the Highschool DxD world, brings her own charm and power to the story.
One popular plotline is the self - insert character gradually building relationships with different members of the harem. For example, they might start by befriending a few characters and then over time, romantic feelings develop. Another is the self - insert getting involved in the battles and power struggles in the Highschool DxD universe while also dealing with the harem dynamics. It could be that they have to prove themselves worthy to be part of the group and in the process, win the hearts of the harem members.