Definitely not. Naruto has a wide fan base that includes people of all ages. 'Lemon' fanfiction often contains inappropriate themes that go against the family - friendly nature of the original Naruto series. So, it's not suitable for all fans, especially those who are more interested in the action, adventure, and positive values presented in the official Naruto works.
Obviously Naruto is one of the main characters, especially in his 'god' form or different multiverse versions of himself. Sasuke might also be a key character as he often has a complex relationship with Naruto. And there could be other characters like Kakashi or Sakura who interact with this new, more powerful Naruto in different ways depending on the plot of the fanfiction.
Naruto watching multiverse fanfiction could have a big impact on his perspective. First, he'd be exposed to a vast array of different Konoha settings. Some might be utopian where there's no war, and others could be dystopian. He'd also see how different his relationships with Sasuke, Sakura, and Kakashi could be. For example, in one fanfic, Sasuke might be a mentor to Naruto instead of a rival. This could make Naruto question the very nature of his bonds and how things could be different. He might even get ideas to improve the relationships in his own world. Also, seeing different power - level Naruto in those fanfictions could either make him feel over - confident or motivate him to train harder.
One common theme is the exploration of different Naruto universes. Since it's multiverse - related, the fanfictions often take Naruto to various versions of his world. Another theme is relationship building. Naruto forms relationships with multiple female characters, so there's a focus on how those relationships develop over time.
One interesting concept is seeing different versions of Naruto characters in alternate universes. For example, a Naruto who becomes a villain instead of a hero. Another concept could be the different power levels and abilities the characters possess in these multiverse settings. Also, the relationships between characters might be completely different, like Sasuke and Naruto being enemies from the start in one universe.
If Naruto watches the multiverse fanfiction, he could gain new perspectives. Maybe he'd see how different choices in other 'Naruto - like' universes led to different outcomes. This could inspire him to think about his own choices in his world, and perhaps even consider alternative ways of doing things in his ninja career.
Definitely Naruto and Sasuke. They are the two main characters in the original Naruto series, and in multiverse fanfiction, their different versions are often central to the stories. For example, a story might focus on a Naruto who was raised differently and how that affects his relationship with Sasuke. Hinata is also popular as she has a lot of potential for character development in different multiverse scenarios, especially in relation to Naruto.
He'd probably be shocked. His world is already full of surprises like different jutsus and powerful enemies, but the multiverse would be on a whole new level. He might not believe it at first and think it's some kind of elaborate prank or illusion.
One tip is to first have a good understanding of the original Naruto universe. This helps you catch all the references in the fanfiction. Also, look for well - rated ones as they usually have better writing quality.