The other characters' reactions would vary widely. Hinata would be very sympathetic. She might be too shy to approach Naruto directly at first, but she'd definitely be thinking about him a lot and trying to find ways to help from the sidelines. Shikamaru would see it as a nuisance at first, but then realize the seriousness of the situation. He might use his intelligence to try and figure out how to get Jiraiya to come back or find a replacement. Tsunade would be furious at Jiraiya for leaving Naruto in such a state. She might take Naruto under her wing more seriously, training him herself or finding the best possible replacement for Jiraiya to ensure Naruto continues to grow as a ninja.
Iruka would be heartbroken for Naruto. He's always been like a big brother to Naruto. He'd likely offer Naruto a place to stay and some words of wisdom. As for Sasuke, he might initially be indifferent, but deep down, he might understand Naruto's pain to some extent, as he also has his own abandonment issues. And the village elders might see this as a potential problem for the village's future, so they might try to find a new mentor for Naruto quickly.
Sakura might be worried about Naruto. She could try to comfort him and encourage him not to give up. She might also be angry at Jiraiya for abandoning Naruto, seeing how much Naruto has been through already. Kakashi, on the other hand, would probably step in more as a mentor. He has his own way of teaching, and he'd want to make sure Naruto doesn't go astray.
Hinata would be heartbroken. She loves Naruto deeply. Her world would shatter. She might try to find out the truth behind his death, not believing that his friends could do such a thing without a good reason. And she would probably hold a grudge against those involved.
One possible plotline could be Naruto feeling extremely lost and having to find his own way to become stronger without their guidance. He might start to question his own worth and abilities, but then he could meet new allies who help him realize his true potential on his own. For example, he could encounter some other outcast ninja who have their own unique skills and together they form a new kind of ninja team that challenges the traditional ways of the ninja world.
Sakura might be a bit annoyed at first. She's used to Naruto being independent and always charging forward, and Gaara's overprotectiveness could seem like it's getting in the way. Kakashi, on the other hand, would probably be more understanding. He'd see the value in Naruto having someone looking out for him, but he might also try to encourage Gaara to let Naruto grow on his own a bit. Sasuke could have a very negative reaction. He might see it as Gaara trying to steal Naruto away from him in a sense, especially if he has his own unresolved feelings towards Naruto.
Many characters would have interesting reactions. Tsunade would likely see it as an opportunity for Naruto to grow and diversify his skills. She might allocate some resources for his sword training. Jiraiya, if he were still alive, would probably be proud and see it as another step in Naruto's journey to become a great ninja. Gaara might view it as a sign of Naruto's ever - expanding power and be even more determined to keep up with him in terms of strength. And the Akatsuki members, if they knew, would probably start to re - evaluate Naruto as a more serious threat now that he has a new and dangerous weapon at his disposal.
He might be angry at first. Naruto has always been a character with strong emotions, and being abandoned would surely trigger his temper.
In such a fanfiction, the plot might involve Naruto turning 'dark' due to feelings of abandonment. He could become bitter and start to question the values Jiraiya taught him. Maybe he'd start using his powers in more ruthless ways, seeing the world as having turned its back on him just as Jiraiya did. He might form alliances with darker characters in the Naruto universe, believing they are the only ones who understand his pain.
Sasuke might be a bit taken aback at first. He has his own complex relationship with Naruto, and seeing him look like Minato could add another layer to it. He might feel a strange sense of déjà vu. Kakashi, on the other hand, would probably be filled with a mix of emotions. He'd see Minato in Naruto and might be more protective or have higher expectations.
In a fanfiction, if Naruto kisses Kaguya mid - fight, many characters would have complex reactions. For instance, the other Kage from different villages would be appalled. They see Kaguya as a threat to the entire ninja world. Naruto's action could be seen as a betrayal. Hinata might be heartbroken. She has deep feelings for Naruto, and this sudden act towards Kaguya would be a huge blow. The Akatsuki members, if they were still around, would probably see this as an opportunity to use the chaos to their advantage. They might try to manipulate the situation to further their own goals while everyone else is distracted by Naruto's strange behavior.
Sakura might be really shocked. She always saw Naruto as a friend and a fellow ninja, and this would be a completely unexpected development. She might be a bit confused about how this would change their relationships. Sasuke, on the other hand, might be more indifferent on the surface but secretly curious. Kakashi would probably be very concerned. He's always been like a mentor to Naruto, and this situation would raise a lot of questions for him about Naruto's future and how this would affect the village. And the elders of the village would likely be in an uproar. They are always worried about the stability of the village, and this would be a huge bombshell that could disrupt the village's order.
Sasuke would likely be enraged. He and Naruto had a complex relationship, and Naruto was like a brother to him. He would probably seek revenge on Sakura immediately. Kakashi, as their teacher, would be deeply shocked and disappointed. He might struggle to understand how Sakura could do such a thing. The villagers would also be in turmoil. Naruto was their hero, and his death at Sakura's hands would cause a great deal of confusion and anger among them.