His old mentor, Iruka, might visit. Iruka has always cared about Naruto. He could bring some supplies and words of encouragement. He might also be worried about Naruto's well - being and want to make sure he's okay living in the cave.
One possible plot could be that Naruto discovers an old scroll that has the lyrics and melody of 'He Lives in You'. As he starts to sing it, he unlocks a hidden power within himself. This power then helps him in a battle against a new and powerful enemy.
There are definitely some out there. It depends on what you're looking for in the fanfiction. If you like stories that are more about Naruto's emotional connection to the song and how it affects his relationships, you might find some really deep and meaningful ones. For example, a story where the song helps him reconnect with a lost loved one in his memories while he sings it.
Maybe some of the younger ninja like Boruto or Sarada could stumble upon Naruto's cave while on a training mission. They could be curious about this strange hermit - like figure in the cave and later realize it's Naruto. This could lead to a mentoring - like relationship between Naruto and the new generation.
He might meet the samurai of Iron Country. These are warriors with different fighting styles compared to the ninjas. Naruto could learn a great deal from them, like their swordsmanship or their sense of honor.
His powers might adapt to the more urban environment. His chakra control could be used in different ways, like using it to jump between tall buildings more easily.
His relationships with his friends in the village would likely become strained. Since he's living in a bunker, he's away from them. They might worry about him and feel left out. For example, Sasuke might think Naruto is avoiding him on purpose.
His character might become more hardened. Kumo is known for its tough ninjas, and living there would expose Naruto to a more cut - throat environment. He may lose some of his naivete and become more calculating in his actions.
Naruto could become more resourceful. In a brothel, resources might be scarce or hard to come by. He'd have to figure out how to get food, shelter, and other necessities. This would force him to think outside the box and use his wits. His values might also be tested as he's exposed to a different set of morals in the brothel. But through it all, he could emerge as a more well - rounded and adaptable character, with a deeper understanding of human nature.
He would adapt through his ninja skills. Suna has a different terrain than Konoha, with more deserts. Naruto would have to learn how to move stealthily in the sand, and how to use the environment to his advantage in combat. He might start training with Suna ninjas who are experts in desert warfare, like learning how to create sand clones or use sand - based jutsu.