Rias from Highschool DxD would be an excellent choice too. Her leadership skills and her role as a devil could be explored in relation to the Naruto characters. She could be intrigued by Naruto's power and try to recruit him into her peerage, or she could learn from Naruto's way of leading his friends and comrades in battle.
I think Naruto himself would be the most interesting. His positive attitude and never - give - up spirit would be really unique in the Highschool DxD world which has a lot of complex power struggles and some rather morally grey areas. He could bring a fresh perspective and also his powerful ninja techniques would make him a force to be reckoned with in battles against devils and angels.
I think Naruto would be the most interesting. His energetic and determined personality would stand out in the Highschool DxD world. He could bring his ninja way of life and values, which are quite different from the devilish and angelic cultures in DxD. His ability to make friends easily might also lead to some really unique interactions with the DxD characters.
I think Naruto himself would be really interesting. His never - give - up attitude and his ability to make friends easily could have a big impact in the Highschool DxD world. He could also learn a lot from the different power structures there. Plus, seeing him interact with the devils and angels would be really cool. He might try to convince them to use their powers for more positive things, like he did with some of the villains in his own world.
Issei could also be a very interesting character to focus on in this fanfic. He is the main character in Highschool DxD. If Naruto and Kuroka enter his world, Issei's reaction to them would be fascinating. He could learn a lot from Naruto's discipline and hard - working nature. And his relationship with Kuroka could also change in new and unexpected ways, adding depth and drama to the fanfic.
Maybe a story where the main characters from both universes have to team up to fight a common enemy. This enemy could be a powerful demon that has somehow found a way to cross over from another dimension. The Naruto characters could bring their combat skills and teamwork, while the Highschool DxD characters contribute their unique powers related to the devil and angel aspects.
Rias Gremory would also be an interesting character to focus on. If she were to interact with Ichigo, her leadership skills and her own goals within the Highschool DxD world could be influenced. Maybe she tries to recruit Ichigo for her peerage, which would lead to all sorts of conflicts and negotiations.
Naruto would be the most interesting. He has such a unique personality and set of skills. His never - give - up attitude would contrast and blend well with the often more self - centered characters in Highschool DxD. He could introduce new values like friendship and loyalty in a more extreme way, and his ninja techniques would be a fresh addition to the battles in the Highschool DxD world.
Naruto and Rias would be an interesting combination. Naruto's positive and determined attitude could contrast with Rias's more calculated and devilish nature. They could learn a lot from each other. Naruto could show Rias about the importance of believing in oneself without relying too much on power, while Rias could introduce Naruto to the complex politics and power structures in her world.
Naruto and Rias would be really interesting. Naruto's straightforward and determined personality combined with Rias' leadership and strategic mind could lead to some great interactions. They could learn from each other's fighting styles and ways of dealing with problems in their respective worlds.
Definitely Naruto himself. His positive attitude and never - give - up spirit would contrast greatly with the more morally ambiguous characters in Highschool DxD. He could also introduce the concept of chakra and ninja techniques, which would be completely new to the Highschool DxD world. His rasengan, for example, would be a very powerful and unique ability in that universe.