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.
The coat might be a key element that drives the plot forward. For example, if the character with the coat is being chased because someone wants the coat, that would create action and conflict.
The fanfiction could explore how Obito's identity revelation affects his relationship with the Akatsuki. Some members may feel used or deceived, while others might see it as an opportunity. It could also show how Obito's true self starts to form new bonds or break old ones within the organization, depending on how his true intentions are perceived.
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 great Rin and Obito fanfiction is 'A Different Path'. It explores an alternate universe where Obito returns to the village earlier. The story delves deep into their relationship, showing how they might have interacted and grown together. The character development is really well - done, and it gives a fresh perspective on their bond.
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.