In this fanfiction, Gabriel could be an original character created by the author. He might be a powerful wizard with a mysterious past. Maybe he was once a great hero or a feared dark wizard, and his connection to Harry is what makes the story so interesting.
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.
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.
One common theme is friendship. Since Naruto is known for his ability to make friends, it's often explored how he and Gabriel Lemon form a strong bond.
One interesting plotline could be Harry's discovery of his true parentage as the son of Gabriel. It might lead to a whole new set of magical abilities and a different relationship with the wizarding world. For example, he could have a unique connection to certain spells or magical creatures that are related to Gabriel's heritage.
There is a 'naruto gabriel fanfiction' where Gabriel visits the Naruto universe in a more comical setting. He tries to understand the strange customs and jutsus there. This kind of story is great for those who like light - hearted reads as it has many humorous moments like Gabriel attempting to do a Rasengan and failing miserably.
One idea could be that Naruto is somehow transported to Gabriel's world. They meet and at first are wary of each other. But as they face common enemies, they start to trust and learn from each other's skills. Naruto could teach Gabriel about chakra and his ninja techniques, while Gabriel might introduce Naruto to angelic powers and their way of life.
Another motive could be related to his pride. If his son has done something that he sees as a disgrace to the family name, in his over - the - top way of thinking, he might resort to hurting him as a form of punishment. This shows how his ego and his ideas of family honor can lead him to such dark actions.
In a fanfiction, it could go either way. Naruto has shown the ability to grow and adapt constantly. He has defeated some extremely powerful foes in his own universe. Gabriel, on the other hand, has powers that are more on the spiritual and divine side. If the fight takes place in the DxD world where there are rules and powers specific to that universe, Gabriel might have the upper hand. But if Naruto can find a way to use his chakra in a unique way against Gabriel's powers, he could also be the stronger one.