Sakura's character could develop a more ruthless side. The ANBU is not a place for hesitation, and she would need to be more decisive. Itachi's character might further explore his relationship with Sasuke in the context of the ANBU. He could be constantly worried about Sasuke's future while performing his duties. Shisui, on the other hand, might develop a closer bond with Sakura, seeing her potential and guiding her in a way that helps her understand the true meaning of being an ANBU operative.
Sakura would likely develop her combat skills further. In the ANBU environment, she would face more dangerous opponents, which would force her to become more strategic. Itachi, already a complex character, might show more of his internal struggle between his loyalty to the village and his love for his family. Shisui could develop in terms of his leadership skills, as he and Itachi might lead Sakura in missions. He could also become more jaded as he faces the darker side of the ninja world.
In an ANBU fanfic, Sakura could start to question her own values. The harsh reality of the ANBU might make her wonder if the ends justify the means. Itachi would continue to grapple with his role in the Uchiha massacre and how it affects his standing in the ANBU. Shisui could develop his ability to trust others. Since the ANBU requires a certain level of teamwork, he would need to rely on Sakura and Itachi more, which could change his somewhat solitary nature.
She would become more stealthy and less impulsive. Since ANBU work requires a lot of secrecy and patience, Itachi's training would force her to change her approach. She might start thinking more strategically and be less likely to jump into a fight without a plan. This could completely transform her from the somewhat brash character she was before.
Sakura would likely be in awe of Itachi and Shisui's skills at first. Itachi, being the more reserved one, might be a bit distant but would gradually warm up to Sakura as he sees her determination. Shisui, on the other hand, would be more friendly and approachable. He might be the one to initiate conversations and break the ice between the three. They could have exchanges about their different ninja backgrounds.
One possible plot could be a story where Sakura, Itachi, and Shisui are all part of the ANBU. Itachi and Shisui could be mentoring Sakura in the ways of the ANBU. They might go on a dangerous mission together, facing powerful enemies. Shisui could use his unique abilities like Kotoamatsukami to gain an advantage, while Itachi's Sharingan and combat skills are also crucial. Sakura, with her medical ninjutsu and growing combat skills, could prove to be a valuable asset in the team.
She could develop a more strategic mind. Shisui and Itachi are known for their intelligence in battle. Sakura would learn from them how to analyze situations better, plan ahead, and anticipate her opponents' moves. This would make her a more well - rounded ninja rather than just relying on her brute strength.
Shisui is known for his cheerful and friendly nature. He would likely be the one to break the ice with Sakura and make her feel welcome in the Anbu team. Itachi, on the other hand, is more reserved. He would respect Sakura's skills but might not be as openly friendly at first. Sakura, being strong - willed, would earn their respect over time with her determination and medical knowledge.
There could also be a more friendly and equal - footing relationship. They might bond over shared interests outside of combat, like a love for a certain type of flower in the village or a particular kind of food. This would bring them closer together on a personal level. Itachi, who is usually reserved, might open up more around Sakura and Shisui, and they could form a tight - knit group of friends who support each other through the difficulties in the shinobi world.
One possible fanfiction could be about Sakura joining an Anbu team that has Itachi and Shisui. Maybe Sakura is a new recruit and she has to learn from the two experienced shinobi. Itachi could be the calm and collected leader, while Shisui is the more easy - going one who helps Sakura adjust to the harsh Anbu lifestyle.
A rogue ninja from a rival village could be the main antagonist. He might be after the secrets of the Sharingan that Itachi and Shisui possess. And he sees Sakura as an obstacle when she tries to protect her comrades. He could have some powerful and forbidden jutsu that makes him a formidable foe for the trio.
To write a good fanfic, focus on character development. Let Sakura grow in her abilities and relationships. Show how Itachi's past affects his present actions when interacting with Sakura and Shisui. For Shisui, explore his loyalty and how that impacts the group dynamic. Also, use vivid descriptions of the Naruto world, like the Hidden Leaf Village or the battle scenes. This will make the fanfic more immersive.
One possible plot could be that Itachi and Shisui are on a mission in the ANBU and they cross paths with Sakura who is also on a mission related to a medical emergency in a war - torn area. They initially have some misunderstandings as Sakura is not used to the ANBU's way of doing things, but eventually they work together. Itachi and Shisui use their combat skills while Sakura uses her medical ninjutsu to save a village from a hidden enemy's attack.