If the grandfather is very warm and accepting, Shikaneji would feel relieved and happy. They might open up more about their relationship and their dreams. Nejire could start chatting excitedly about their future together, and Shinsou would relax and join in the conversation more. However, if the grandfather is not so friendly, they would be disappointed and perhaps a bit defensive.
In this fanfiction, the meeting with the grandfather could also be a source of conflict. Perhaps the grandfather has certain expectations or traditions that seem to be at odds with Shikaneji's relationship. This would create drama as they try to navigate their feelings while also dealing with the grandfather's views.
In a Shika Neji AU fanfiction where they meet their grandfather, it might be a very emotional encounter. The grandfather could be a symbol of their roots and heritage. He might have a unique power or ability that he passes on to them, either literally or through some wise advice. For instance, he could teach them how to face their inner demons or how to make the right decisions in difficult situations, which would then shape their characters and their roles in the fanfiction's plot.
Thor would likely be the most affected. He has a history with Fenrir as it is from Asgardian mythology. He might be cautious at first, but also feel a sense of kinship. Iron Man would probably be all about analyzing Fenrir, trying to figure out its weaknesses and strengths. Captain America would be on guard, ready to defend his team, but also open to the idea of Fenrir not being an enemy if proven so.
Tony Stark would probably be very intrigued. He'd want to study Loki's Jotun form, maybe even make some snarky comments about his blue skin. Steve Rogers, on the other hand, would be more cautious. He'd be ready for any potential threat that Loki might pose.
Meeting their grandfather can make them more mature. For example, if their grandfather has seen a lot in his life, he can share those experiences with Shika and Neji. This could make them more cautious in their actions and think more about the consequences.
Hermione would probably be very curious. She would start asking the gods all sorts of questions about their magic and their history. Ron, on the other hand, might be a bit intimidated at first but would soon warm up when he realizes they can offer some help against the Dark forces.
Thor might be conflicted. He'd see his nephew/niece but also remember Loki's treachery. Iron Man would probably be sarcastic at first, making remarks about the family genes. Captain America would be more cautious and diplomatic, wanting to give her a chance but also being on guard. Black Widow would try to read her body language and motives right away.
Some of the gaang members might be very excited. Aang, being the Avatar, would probably be curious to learn from Ursa. He could ask her about the Fire Nation's history and how it relates to the balance of the world.
Captain America would probably be very reflective. He might see his past self as a reminder of his long journey and how much he has changed. He could try to offer some words of wisdom to his younger self.
The Avengers might react in different ways. Steve Rogers would probably be polite but firm in getting to know Peter's boyfriend. He'd want to ensure that he was a good influence on Peter. Thor, on the other hand, might be a bit more boisterous. He could either be really friendly and enthusiastic, or his loud and powerful presence might accidentally scare the boyfriend a bit.