A simple idea could be that Naruto is reincarnated as a student in the High School DxD world with some archangelic powers. He would have to deal with the typical high school drama along with the supernatural threats in that world. His positive attitude might be a shock to some of the more cynical DxD characters.
Perhaps there could be a prophecy in the High School DxD world about a 'foreign hero' which turns out to be Naruto. The archangels initially oppose his arrival, fearing he'll disrupt the balance. But as Naruto proves his good intentions by saving some of the students from a powerful enemy, they start to accept him. His unique abilities like summoning toads could be a huge advantage in the battles against the devils and fallen angels in the DxD world.
In a Naruto and High School DxD crossover fanfiction involving an archangel, it could be really interesting. Maybe the archangel has powers that are similar to some of the shinobi abilities in Naruto. For example, the archangel might have a 'heavenly chakra' that is like the normal chakra but with more divine properties. It could also be that the archangel has a role in the DxD world similar to Naruto's role in his own world, like a protector or a catalyst for change.
Well, a fanfiction like this could be really interesting. One way it could work is by having a character from Naruto world somehow end up in the High School DxD universe and interact with the archangels there. Maybe Naruto himself could gain some new powers related to the angelic realm in this crossover. He could learn about different hierarchies of angels which are very different from the ninja system he's used to.
Naruto characters' reactions would vary. Shikamaru would likely find the whole situation troublesome. He doesn't like getting involved in things that are too complicated. But Naruto would approach the archangel with his usual enthusiasm. He'd want to be friends and learn about the archangel's world. Hinata would be shy but also intrigued. She might see the archangel as a very noble and powerful being. And Kiba with Akamaru would be a bit more aggressive in their approach, ready to defend themselves if needed but also eager to know more about this new entity.
In this fanfiction, Naruto could be on a mission to find a way back to his own world. Along the way, he teams up with Issei and his group. Together, they face various challenges, including battles against powerful devils. Naruto's sage mode could be a crucial factor in these battles, and he might also learn some new skills from the DxD world.
One idea could be Naruto being summoned into the High School DxD world during a battle. His unique ninja skills would shock the devils and angels in that universe. He might form an unlikely alliance with Issei, perhaps teaching him some ninja techniques in return for learning about the Sacred Gears.
One idea could be that Naruto is somehow transported to the world of High School DxD. He could use his ninja skills, like shadow clones, in the battles that take place in the DxD universe. Maybe he'd form an alliance with Issei and his group, and teach them some ninja techniques to fight against the devils and fallen angels.
Another possibility is a story where the power - up systems of both Naruto and High School DxD are combined. For example, Naruto could learn about the Boosted Gear and use it in a new form of his Rasengan. Or Issei could gain chakra and learn some basic ninja techniques. This would create an interesting dynamic as they face common enemies.
One idea could be that Naruto is somehow transported to the world of High School DxD. He could use his ninja skills, like shadow clones, in the battles against the devils and fallen angels in that universe. Maybe he'd form an alliance with Issei and his group, teaching them some unique ninja techniques.
One idea could be a crossover where Naruto is somehow transported to the world of High School DxD. He meets Gabriel, and they team up to face a common threat. Maybe a powerful devil or a new, unknown enemy. Naruto's ninja skills could be a great asset in the battles of the DxD world.
One idea could be that Naruto, with his unique powers, somehow gets transferred to the world of High School DxD. He could be seen as an 'Immortal God' in that universe due to his chakra and abilities. Maybe he teams up with the main characters of DxD to fight against common enemies. For example, his shadow clone jutsu could be used in creative ways during battles in the DxD world.