Well, perhaps the person Hinata is kissing is under some kind of mind - control. In the fanfic, Naruto sees this and immediately jumps into action to save Hinata from an unwanted situation. He has to fight off the source of the mind - control and then deal with his own feelings of jealousy and protectiveness towards Hinata.
One possible plot twist could be that Hinata is kissing someone as part of a mission. Maybe she has to pretend to be in love with a character to gain information. Naruto, seeing this, initially misunderstands but then later discovers the truth and respects Hinata's dedication to the mission.
Naruto might be shocked at first. He could stand there frozen, unable to believe what he's seeing. His face would probably show a mix of confusion and hurt.
One possible plot could be that Hinata accidentally stumbles upon Naruto's memories during a mission. Maybe they are in a strange place where memories are made visible, and Hinata starts to understand Naruto on a much deeper level. She sees his lonely childhood, his determination to be recognized, and his dreams for the future. This newfound understanding could strengthen their relationship and make Hinata more determined to support Naruto in his goals.
It could be a really sweet fanfic. Naruto and Hinata have a long - standing relationship in the Naruto series. Their kiss in a fanfic might happen after a big battle where they realize their deep feelings for each other. Maybe Naruto finally sees Hinata in a new light and can't resist kissing her, and it could be a moment filled with passion and love.
There are a lot of things that could occur. Naruto and Hinata could start a new adventure in heaven. They could meet other deceased friends and have a big reunion. Their relationship could deepen even more as they are free from the dangers and politics of the Ninja world. They might also be given some sort of special task or mission in heaven, which would bring them even closer together while they complete it.
There are probably some. Fanfic writers often explore the relationship between Naruto and Hinata in different ways. They might write about their first kiss, or a romantic moment where a kiss occurs. However, the quality and content can vary greatly among different fanfics.
It could symbolize a new chapter in their relationship. Before, Naruto was mostly focused on his goals and being recognized in the village. But after facing Pain, he might have a new perspective on life and love. The kiss with Hinata could be the start of a deeper, more romantic connection, showing that he's ready to explore his feelings for her and let someone be close to him in a different way.
Maybe in the fanfic, Naruto sees a future where Konoha is destroyed. This makes him determined to change the future. He could start by strengthening the village's defenses, forging new alliances, and also trying to figure out the root cause of the destruction in the future he saw. He might also try to uncover any hidden threats within the village that could lead to such a catastrophe.
One possible plot reason could be for Naruto to experience a great loss that changes his character completely. Maybe it's part of a dark plot where the enemy is so powerful that they manage to kill Hinata right in front of Naruto. This would fuel his rage and determination to become even stronger and seek revenge. Another reason could be related to some sort of sacrifice. Hinata might sacrifice herself to save Naruto or someone else important, and Naruto has to deal with the guilt and grief of her death.
In this fanfic situation, Castle seeing Kate kissing another man could be a misunderstanding. Maybe the man is an old friend or relative of Kate's and it's just a friendly kiss that Castle misinterprets. So, the plot could then be about clearing up this misunderstanding and Castle and Kate getting back on track.
One possible plot twist could be that Naruto unlocks the Rinnegan in a moment of extreme emotional turmoil. For example, when he witnesses the death of a very close friend like Sasuke. This could trigger a dormant power within him that was previously unknown. Another aspect could be that the way he uses the Rinnegan is completely different from how others have. He might use it to bring peace in a more unique way, like using its power to erase negative emotions from people's hearts.