One reason could be political. Maybe the two clans or villages that Naruto and Sasuke are associated with want to strengthen their alliance. By marrying their most powerful members, they hope to ensure peace and cooperation.
One reason could be for power. Combining their strengths through marriage could make them an even more formidable force. Maybe Sasuke saw it as a strategic move to protect their village or to face some greater threat that they are not aware of yet.
One possible reason could be jealousy. Maybe fem Sasuke is jealous of Naruto's natural charisma or his ability to make friends easily. Another reason might be related to their different goals. If fem Sasuke has a very different view of how to save or change the ninja world compared to Naruto, it could lead to hatred.
At first, Naruto would be in disbelief. She has always seen Sasuke as a friend or a rival, not a marriage partner. So, she would likely be very vocal about her opposition. She might gather her friends, like Sakura and Kakashi, to support her cause. She could also try to appeal to Sasuke's sense of justice. Since Sasuke has his own code of ethics, he might also not be happy about this forced situation. Naruto could use this to try and find a way to break free from this unwanted marriage.
It could also be due to a power struggle. Fem Sasuke might be jealous of Naruto's growing power and influence. In some fanfictions, characters can be driven by envy, and she might see Naruto as a rival that needs to be put in her place, so she ends up hurting him.
One reason could be the author's desire to create drama. By having such a betrayal, it amps up the emotional turmoil. Another could be to explore different relationship dynamics. Maybe the author wants to see how Naruto would react to such a situation, which is a way of testing the limits of their bond.
Well, Naruto has always been there for Sasuke in the original story. In fanfiction, Fem Sasuke might secretly like Naruto because she sees his loyalty. He's constantly trying to bring Sasuke back to the right path. This loyalty could translate into a deeper affection in the fan - created stories.
Well, it could be that an ancient prophecy in the Naruto world dictates that Naruto and fem Sasuke must marry. Naruto might be in a tough situation because he has his own dreams and goals. However, fem Sasuke could also have her own reasons for going along with it. Maybe she wants to use this opportunity to change the ninja world in some way. As they live together, they'll face many challenges from their friends and family who might not be fully on board with this arrangement, but they could grow closer through these difficulties.
Perhaps Fem Sasuke in this fanfiction has a different view of the world. She might believe that Naruto is a threat to her goals or to the future of the ninja world she envisions. It could also be that she has some deep - seated emotional pain that she blames Naruto for, and that leads her to kill him.
One possible plot could be that Sasuke realizes his deep connection with Fem Naruto over time. Maybe they go on various missions together and he starts to see her in a new light. As they face challenges side by side, his feelings grow into love and he decides he wants to marry her. He then has to overcome the initial shock of the village and their friends, as it's an unexpected pairing.
One reason could be that Sasuke really values Sakura's friendship and is afraid of losing it to someone else. Maybe she sees others getting closer to Sakura and feels left out.