The curious characters would be engaged. They would be eager to explore all the new elements in the fanfiction. They might start asking questions like 'Why did the author make the Grinch do that?' or 'What if this happened instead?' and really get into the details of the story.
The cynical characters might be critical. They could pick apart the plot holes or the unrealistic elements in the fanfiction. They might say things like 'This doesn't make any sense compared to the real Grinch story.'
Hero characters might analyze it from a moral perspective. They could either approve or disapprove of the way the story is told in the fanfiction depending on whether it aligns with their sense of right and wrong. Villain characters, on the other hand, might look for ways to use the ideas in the fanfiction to their advantage, like new ways to create chaos.
The more philosophical fanfiction would intrigue the Jedi Masters. Yoda, for instance, would probably nod his head and say 'Much to think about, there is in these words.' They would see it as an opportunity to further explore the concepts of the Force, good and evil, and the nature of the Star Wars universe. However, the average stormtrooper might not understand it at all and just shrug it off as some strange mumbo - jumbo.
For heroic - centric fanfictions, they would likely be disdainful. Since they oppose heroes, seeing stories that glorify heroes would annoy them. They might scoff at the idealized versions of heroes in those fanfictions.
Some might laugh. They could find the humorous takes in the fanfiction really entertaining. Maybe there are some comical interpretations of their actions or dialogues that they themselves didn't expect.
Some characters might laugh. They would see the humorous side of how fans have twisted and turned their stories. It could be like seeing a new, comical version of their own lives as depicted in the musical.
They could have a range of reactions. Naruto would likely be excited and eager to see new stories about his world. He loves adventures and would be interested in seeing different takes on his life.
Some characters might be shocked. They may not expect such wild interpretations of their lives and relationships.
Naruto would be thrilled. He loves being the center of attention and seeing all these stories about him would make him feel even more important. He'd probably want to meet the writers and tell them how cool he thinks their ideas are.
They might be confused at first. RWBY has its own unique lore and concepts that are different from many anime. So anime characters may need time to understand things like Grimm and Huntsmen. For example, if Goku from Dragon Ball was watching, he'd probably be like 'What are these strange monsters?'.
Naruto would likely be excited. He loves his son so much that seeing different stories about Boruto would be like seeing different potential futures for him. He might even get some inspiration from the fanfiction to give Boruto some advice in real life.