His other friends like Shikamaru would be in shock. Shikamaru, who is usually calm and collected, would struggle to come to terms with Naruto's death. They would all have to deal with the loss of the village's hero and a great friend, and it would likely change the dynamics of the entire group.
Sakura might be in shock at first. Unable to believe that Naruto, who has always been so strong - willed, could have ended his own life. As she processes it, she could become angry, not at Naruto but at herself and the situation that led to this tragic outcome.
This is a really dark concept. In fanfiction, such a scenario might be written to explore extreme emotional distress. Maybe the author wants to show how much pressure Naruto has endured secretly, and on his birthday, which is supposed to be a happy day, it all becomes too much to bear. However, in the original Naruto story, Naruto is a character full of hope and perseverance, so this is a very different take.
One common theme is unrequited friendship. Naruto's deep - seated friendship for Sasuke not being reciprocated in the way he hoped could lead to his downfall. Another theme could be the idea of sacrifice. Naruto may sacrifice himself believing it will save Sasuke from his dark path.
In this type of fanfiction, a major theme is often the fragility of the male ego in the face of unrequited love. Naruto, despite his strong exterior, is broken by Sakura's lack of romantic interest. Another theme could be the idea of lost hope. Naruto may have hoped for so long that Sakura would come to love him, but when that hope is finally extinguished, he sees no reason to continue living. Additionally, themes of loneliness and isolation might be present as Naruto may feel completely alone in his unrequited love for Sakura.
It could be a miscommunication. Maybe Hinata said something that Naruto completely misinterpreted in a very negative way, like she didn't love him anymore or she blamed him for something major. This misunderstanding could be so great that Naruto loses hope and takes his life.
One possible reason could be extreme heartbreak. If in the fanfic, Sasuke does something unforgivable like completely rejecting Naruto's long - held friendship and trust, it might push Naruto over the edge. He has always placed great importance on his bond with Sasuke, and if that is shattered in a way that seems irreparable, it could lead to his self - destruction.
This is a very dark and unexpected plot. One possibility could be that Naruto is burdened by some extreme situation related to Hinata. Maybe he feels responsible for her getting into a great danger or a situation where her life is ruined, and his sense of guilt overpowers him, leading to this tragic end.
In the original Naruto storyline, Naruto is a character full of hope and determination. He would never give up easily, especially not to the point of taking his own life. So in this fanfic, it's a huge deviation as it goes against his core trait of perseverance. He has faced countless difficulties and setbacks in the original story but always found a way to keep going.
Yes, such fanfictions exist. In these fictional scenarios, Naruto might kill himself because of Sasuke for several reasons. Naruto's whole life has been centered around Sasuke to some extent. If he feels that he has failed in his mission to bring Sasuke back to the right path and that the situation has become so dire that the only way to atone for his 'failure' is through his death, he might do it. Also, if Sasuke were to cause harm to someone Naruto holds dear, like the village or his other friends, and Naruto feels powerless to stop him in any other way, he could choose to end his own life as a last resort.