One way is through shared missions. If they are assigned to a joint mission, they will be forced to work together. During this time, they can start to appreciate each other's skills and personalities. For instance, Sakura's intelligence and quick thinking can complement Gaara's more stoic and powerful approach.
Their relationship could also develop through mutual understanding of their past traumas. Sakura has faced her own set of challenges with Sasuke's departure and her struggle to be recognized as a strong kunoichi. Gaara has his history of being feared and alone. By sharing these experiences, they can form a deeper bond. This could be shown in a fanfiction where they sit down and have a heart - to - heart conversation about their pasts.
In fanfiction, their possessive relationship can be developed through external threats. Let's say there's a new enemy who is specifically targeting Sakura because of her relationship with Gaara. Gaara becomes extremely possessive and protective, not allowing her out of his sight. Sakura, seeing his worry, also becomes possessive of their time together and doesn't want to be separated from him even for a moment. As they face this threat together, their possessive feelings grow stronger and their relationship deepens.
In such a fanfiction, their relationship could develop in a rather complex way. Gaara, due to his past traumas, would be hesitant to open up completely. Sakura, with her empathetic nature, would try to understand him. They would start with small conversations about their villages and their dreams. As they share more, they realize that they are both lonely in their own ways. Their relationship would then progress as they support each other through difficult times, like when Gaara has to deal with political unrest in the Sand Village and Sakura has to face her own insecurities within the Leaf Village.
In fanfiction, their relationship can be developed through shared experiences. For example, they could be trapped in a mysterious dimension together. During their time there, they have to rely on each other to survive, which makes them trust one another more.
Gaara can be developed to be more outgoing in fanfiction. Instead of his usual reserved self, he could start to make more friends at high school because of Sakura's influence. Sakura, on the other hand, could be developed to be more assertive in her feelings towards Gaara. Maybe she starts to take the lead in their relationship instead of being shy.
They could be paired up for a diplomatic mission to another ninja village. Along the way, they encounter various cultural differences and political intrigues. As they navigate through these situations together, they grow to respect and care for each other more.
Their relationship could start with mutual respect for each other's skills. Sakura admires Anko's boldness and combat skills, while Anko respects Sakura's intelligence and medical abilities. This could lead to them training together, gradually becoming friends and sharing their life stories.
In fanfiction, the possessive relationship can start with Kakashi noticing Sakura's growth and potential. He might become possessive as he sees her as a valuable asset to the team and someone he wants to protect at all costs. For example, he could start giving her special training, but in a way that shows his possessive nature, like not allowing others to interfere with her training time.
In a realistic development, they could start as comrades. Gaara, as the Kazekage, would have certain responsibilities, and Matsuri would be one of his loyal shinobi. As they work together on village projects, they start to notice each other's strengths and weaknesses. For instance, Matsuri might admire Gaara's leadership skills, and Gaara might notice Matsuri's dedication. Over time, these feelings could turn into something more romantic.
Another way is through their mutual friends. If Naruto, for instance, asks them both to help with a project for the village, like building a new training ground. Konohamaru and Sakura would have to work together, communicate, and make decisions. They would start to see each other's good qualities. Konohamaru would admire Sakura's determination and Sakura would be impressed by Konohamaru's growth as a ninja. This would gradually develop their relationship into a closer friendship.
They could start by having more in - depth conversations. For example, Naruto could share his dreams for a more peaceful ninja world with Sakura, and Sakura could talk about her hopes for the growth of Konoha's medical facilities. This would deepen their understanding of each other.