Maybe a story about a character from Naruto ending up in the DxD world and having to adapt to their culture and power system. They could bring some of their ninja skills and use them in unique ways in the new world.
A plot where the characters have to team up to fight a common enemy that threatens both their worlds. For example, a powerful dark force that can manipulate both chakra and magic. This would force them to learn about each other's abilities and work together.
Perhaps Naruto has a unique power that is related to both worlds. He could form a team with some of the DxD characters like Issei. They could go on adventures together, fighting against common enemies. His rasengan might be enhanced by the magic in the DxD world.
One idea could be that Naruto, through some sort of interdimensional rift, ends up in the world of Highschool DxD. Ravel could be intrigued by this strange new being with his unique powers. Maybe Naruto has to team up with Ravel to face a common enemy in the DxD world, like a rogue group of devils. His ninja skills would be a novelty there and could help them in battles.
One idea could be that Naruto somehow gets transported to the High School DxD world and has to use his ninja skills in the battles there. Maybe he teams up with Issei and they combine their powers in a unique way.
One plot idea could be Naruto being transferred to the Highschool DxD world and having to adjust to the new school environment while also dealing with the supernatural elements. He could form an unexpected friendship with Ophis, perhaps over their shared experiences of being different from the norm in their respective worlds.
Well, a plot could involve Naruto learning about the Devil Pieces in the DxD world and trying to figure out a way to use his chakra in a similar way to reincarnate or empower allies. Or maybe some of the DxD characters end up in the Naruto world and have to adapt to the different power systems there, like learning how to use ninjutsu.
One idea could be that Naruto and Sasuke are transported to the DxD world and they have to learn the new rules and powers there. They might team up with some of the DxD characters to face a common enemy.
A possible plot is that Naruto, mute as he is, discovers a new form of magic in the DxD universe that is related to silent communication. This could lead to him becoming a very powerful figure as he can communicate secretly with his allies during battles. Also, his backstory from Naruto could be intertwined with the DxD lore. For instance, his experience with loneliness in his own world could make him more empathetic towards the devils in DxD who are often misunderstood. He could then try to bridge the gap between different factions in the DxD world.
Well, a plot could revolve around a mystery that involves both worlds. Maybe there is an ancient artifact that has the power to disrupt the balance between the Naruto universe and the Highschool DxD universe. Characters from both sides have to work together to find and protect this artifact. This would lead to a lot of character development as they learn about each other's cultures and values while on this quest.
One possible plot idea could be a crossover where Naruto characters gain powers from the DxD universe and have to face a new, powerful enemy. For example, Naruto could learn about the Devil Pieces system and use it to strengthen his allies in Konoha. Another idea might be a story where a character from DxD ends up in the Naruto world and has to adapt to its ninja culture while also using their own unique abilities to help or hinder the existing power balance.
One idea could be that Naruto finds himself in the DxD world and tries to use his ninja skills in the battles against devils and fallen angels. Maybe he forms unique alliances with the various factions in the DxD world, like teaming up with Rias Gremory's peerage and teaching them some ninja techniques.