In an 'Obito kills Kakashi' fanfiction, it could start with a long - standing grudge. Maybe Obito discovers some new information that he believes Kakashi has been hiding from him all these years. This enrages him so much that he decides to take revenge and kills Kakashi in a fit of rage during a battle.
Some fans would be really shocked and sad. Kakashi is a very popular character, and his death at the hands of Obito would be a huge blow to many. They might feel angry towards the author for creating such a tragic scenario.
In this alternate storyline, it could lead to major changes in their relationship and the overall plot. Maybe Obito's feelings would prevent him from going down the dark path he did originally.
Naruto could be one of his allies. Naruto has this knack for seeing the good in people and would probably be willing to give Obito a chance to redeem himself. Also, Sakura, with her skills as a medic - ninja, could be an ally. She might help heal Obito if he was injured during the war and see the potential in him to be a force for good.
One possible motive could be to use Sakura as a bargaining chip. If he has some sort of plan against Naruto or the Hidden Leaf Village, Sakura, being a close comrade of Naruto, could be very useful. He might think that by restraining her, he can force Naruto to come to a certain location or make concessions.
One popular sakura and obito fanfiction is 'The Unseen Bond'. It delves into a world where Sakura discovers Obito's hidden past and tries to help him find redemption. Another great one could be 'Sakura's Encounter with Obito', which focuses on their chance meetings and how it gradually changes their relationship. And there's also 'A New Path for Sakura and Obito' that shows them working together to face challenges in the ninja world.
The sad story of Obito and Rin is a key part of the Naruto narrative. Obito was a young ninja with big dreams and a huge crush on Rin. When Rin was seemingly killed in front of him, it shattered his world. He thought that the ninja world was full of pain and betrayal. This led him to be influenced by Madara. He became one of the main antagonists, all because of his love for Rin and the unbearable pain of losing her. His journey from a hopeful young ninja to a vengeful villain is a tragic consequence of Rin's death.
One of the best elements is the exploration of their contrasting personalities. Sakura is often seen as strong - willed and determined, while Obito has a more complex and troubled past. Their interactions can lead to some really interesting character development. Another element is the potential for redemption arcs, especially for Obito. Sakura can be a catalyst in his journey towards redemption. Also, the fanfiction can play with the idea of their different loyalties in the ninja world and how they navigate through that.
The main character is Obito without a doubt. The other main character in the 'obito love story' could be a character from a different clan. Their different backgrounds would add more depth to the story. For instance, if Obito is from the Uchiha clan and the love interest is from the Hyuga clan, their relationship would be full of cultural and clan - related tensions, making their love story all the more interesting.