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.
Naruto's transformation abilities like Nine - Tails Chakra Mode would also be very impactful. The increased power and the unique appearance of this mode would intimidate his enemies. In the world of DxD, where appearances and auras play a role in battles, this could be a great advantage. He could also use the chakra of the Nine - Tails to heal himself, which is something that could come in handy during long and tough battles in Issei's world.
Also, the oc might have different goals than Issei. While Issei is often focused on his perverted desires as well as becoming stronger to protect his friends, the oc could have a more noble or self - centered goal like finding a way back to their original world or using the power in this new world for personal gain in a non - perverted way. This contrast in motives can create a lot of tension and interesting plot developments.
In terms of the overall plot, Naruto's presence as Issei could change the power dynamics. He has experience in dealing with all kinds of powerful foes in the Naruto universe. So, in the world of DxD, he might not be as easily pushed around as Issei was at first. He could also bring a new sense of justice and values from the ninja world, which could influence the other characters and how they view different situations.
Sure. 'High School DxD: Reborn as Issei' is quite popular. It often explores different scenarios where the protagonist is reborn as Issei and has to navigate the complex world of the series in new ways. Another one could be 'Reborn as Issei: A New Path', which might have unique plot twists and character developments that are different from the original series.
Obviously, the oc reborn as Issei would interact with Rias Gremory. She is a central character in the High School DxD world and as Issei is part of her peerage, the oc in Issei's place would have a lot of interaction with her. This could range from her guiding the oc in the ways of the devils to them having some sort of romantic or at least a very close friendship relationship.
I'm not entirely sure as the description is rather unclear. It could potentially be about a character named Issei in the 'DxD' universe and some sort of action related to a fanfiction about him. Maybe it's about exploring or creating a fan - made story where Issei is involved in a stroking action, though without more context it's hard to be specific.
It could be his fellow team members. They might betray him out of greed for power. Maybe they thought that by getting rid of Issei, they could gain more resources or a higher position within their group.
Issei could react with anger. He might lash out at his partner and the person they cheated with. He could also become very confrontational, demanding explanations and apologies.
Rias could be a main character. She has a strong connection with Issei and in a fanfiction about him as the Prince of Darkness, she might play a role in helping him control his new power or deal with the political ramifications of his new status.