Well, perhaps Naruto discovers an ancient relic during one of his missions that somehow fuses with him and gives him Kakuja - like abilities. His friends initially fear him, but Naruto is determined to show them that he's still the same person. Meanwhile, a new enemy emerges who is also related to the origin of the Kakuja power. Naruto has to not only master his new form but also uncover the mystery behind it to defeat this new threat and restore peace to the ninja world.
The plot could start with Naruto being transported to a different dimension where the concept of Kakuja exists. There, he is forced to adapt to this new power within him to survive. He meets new allies and enemies in this dimension. As he learns more about the Kakuja and its powers, he starts to bring some of its aspects back to his own world when he finally finds a way to return. But this new power causes unrest in Konoha as some see it as a threat, and Naruto has to convince everyone that it can be a force for good.
Yes, there are likely fanfictions out there with the concept of 'Naruto has a Kakuja'. The Naruto fandom is vast and creative, and fans often come up with unique crossovers and concepts. Some fanfic writers might be inspired to combine Naruto's world with the idea of a Kakuja from other series or create their own unique take on it within the Naruto universe.
One possible plot could be that Naruto discovers Vulpix lost in the woods near Konoha. He decides to take care of it and Vulpix becomes his loyal sidekick, using its fire - based attacks to help Naruto in battles.
One possible plot could be that Naruto discovers he has Byakugan abilities through some strange encounter. Maybe he meets an ancient sage who bestows this power on him. This new power would completely change his fighting style. He could start using the Byakugan's long - range vision and near - perfect perception of an opponent's moves in his battles. It would also create an interesting dynamic within his team, as they would have to adjust to Naruto's new abilities.
Maybe the Sanbi was sealed inside Naruto by mistake or as a last - ditch effort to save it. Naruto then has to deal with the sudden influx of the Sanbi's chakra and the attention it brings from various ninja clans who want to either use it or destroy it. He has to train hard to master the Sanbi's abilities and prove that he can be a responsible host. As he does this, he also forms a unique bond with the Sanbi, which changes his perspective on power and responsibility. This could lead to him becoming an even more powerful and respected ninja.
One possible plot could be Naruto using Kotoamatsukami to end a long - standing war. He could use it to make the leaders of the warring factions see reason and come to a peaceful agreement.
In a 'Naruto has Nuibari' fanfiction, the plot might involve Naruto accidentally coming into contact with Nuibari in a mysterious way. This weapon then starts to have an influence on his mind, showing him visions of past battles it was involved in. Naruto has to figure out how to control this connection and the power of Nuibari. As he does so, he realizes that there is a hidden secret about the weapon that is linked to his own family history. He then embarks on a journey to uncover the truth about Nuibari and his family, all while using the weapon to protect his village from threats that are starting to emerge because of his new - found power.
One possible plot could be that Naruto discovers a hidden portal that leads to the world of Bleach. There, he encounters the Senbonzakura and somehow forms a connection with it. He then has to learn how to control its power to get back to his own world. Along the way, he meets characters from Bleach and they either help or hinder his journey.
In a 'Naruto has a gun' fanfiction, the plot could involve Naruto getting the gun during a mission in a foreign land. The gun could be a symbol of power there. Naruto then has to face the moral dilemma of using such a weapon. He might face enemies who are also after the gun because of its power. His ninja skills would be combined with the new threat and advantage of the gun, leading to some intense battles and strategic decisions.
Well, it could be about Naruto teaching his baby ninjutsu in a really cute way. Maybe the baby has some special power that even Naruto is amazed by.
Maybe the fanfiction could be about Naruto's child feeling the pressure of living up to their father's great name. They struggle in their ninja training because everyone expects them to be as good as Naruto right away. Along the way, they meet a group of outcasts and together they learn to find their own strength, different from Naruto's, and prove themselves to the village.