To develop Naruto's character in this fanfiction, he could face challenges that require him to use his wits more than his physical strength, which he learns from Gabriel. Gabriel's character could develop by learning about Naruto's past, his struggles, and his dreams. This could make Gabriel more involved in the mortal world and its affairs. He might even start to question some of the angelic rules and traditions he has always followed.
Naruto would probably be very curious about Gabriel. He's used to dealing with all kinds of strange and powerful beings in his own world, but Gabriel with her angelic nature would be something new. He might start by asking a lot of questions about her powers and the world she comes from.
One possibility in this fanfiction is that Naruto is summoned to Serefall by Gabriel for a special mission. Naruto's combat skills would be put to the test against new and powerful enemies in Serefall.
There could be so many amazing stories in a fanfiction involving Naruto, Gabriel and Serefall. Maybe Naruto could team up with Gabriel to save Serefall from some great danger. Their unique abilities combined would make for an epic adventure.
The power dynamics can be really fascinating. Naruto has his chakra - based powers like Rasengan and Sage Mode, while Gabriel has divine powers. Fanfictions explore how these powers interact, whether they combine in new ways or clash in battles. For example, in some fanfictions, they might use their powers together to defeat an extremely powerful foe that neither could handle alone. Also, the character development can be unique. Naruto's journey of growth and Gabriel's possible change in perspective when exposed to the ninja world add depth to the stories.
One idea could be a crossover where Naruto's world is merged with the one that Gremory and Gabriel exist in. Naruto, with his strong will and ninja skills, could form an alliance with Gremory, who might be from a noble demon family, and Gabriel, an angel. They could fight against a common enemy that threatens both their realms, like a powerful dark force that wants to disrupt the balance between the ninja world, the demon world, and the angelic realm.
Another theme is the idea of power and growth. Naruto is constantly striving to become stronger, and when Gabriel enters the picture, there could be new ways for Naruto to gain power or a new understanding of his own abilities. Gabriel himself might also experience growth in terms of his understanding of the mortal world.
One possible fanfiction could be about a crossover where the characters from Highschool DxD and Naruto are transported to a world where they meet Gabriel. Maybe they team up to fight a common enemy. For example, the devils from Highschool DxD and the ninjas from Naruto could combine their powers under Gabriel's guidance to defeat an ancient evil that threatens all three of their realms.
A common theme could be the clash of different worlds. Naruto's ninja world and Gabriel Lemon's world, whatever it may be in the fanfiction, often collide. This leads to interesting cultural and power - based interactions.
Obviously Naruto as the main character. Gabriel would be a key figure, perhaps appearing in flashbacks or even in a more present form to guide Naruto. There could also be other Naruto characters like Kakashi, who might be intrigued by Naruto's new heritage and try to help him understand and control it.