One idea could be a story where Sakura, as a skilled medic, is tasked with treating Itachi and Shisui during a difficult mission. She discovers their complex pasts and bonds with them over time, leading to new alliances and friendships.
Well, you could go for something like 'Itachi and Shisui: A Lemon - Infused Adventure'. This title gives the idea that there's something unique and perhaps a bit zesty about their relationship in the fanfiction. Another option could be 'Lemon - Hued Memories of Itachi and Shisui', which implies that the story might be filled with memories that have a certain flavor, like the sour - sweet taste of a lemon. And also, 'Itachi, Shisui and the Lemon - Scented Plot' could work, suggesting that the plot has an element related to this lemon concept.
Sakura's amusement could actually make Shisui more likely to continue annoying Itachi. Since she finds it funny, Shisui might see it as a sign that his actions are acceptable and entertaining. This could potentially strain the relationship between Shisui and Itachi further if Itachi doesn't like being the target of Shisui's annoyance.
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.
One common theme is loyalty. Given their status as Uchiha, loyalty to the clan and to each other is often explored. For example, in many fanfics, they will go to great lengths to protect one another because of their loyalty.
Another theme is sacrifice. Given their fates in the original story, fanfictions often play around with the idea of how much they are willing to sacrifice for each other and for the greater good. It could be sacrificing their own lives or their own happiness for the other.
A common theme is time - travel. For instance, Sakura might travel back in time and meet a younger Itachi and Shisui. This allows for interesting plot developments as she tries to change the future or just understand their past better. Also, the theme of redemption can be found. Maybe Itachi or Shisui have made some mistakes in their past and Sakura helps them find redemption through their interactions with her.
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 good fem Itachi x Shisui fanfiction is 'The Bond Beyond'. It beautifully portrays their relationship in a unique way. The story focuses on how their friendship evolves in a world where Itachi is female. It has great character development and some really touching moments.
In 'Shisui x Itachi' lemon fanfiction, a frequent theme is the secrecy and forbidden nature of their relationship. Given their positions within the Uchiha clan and the overall Naruto world, the idea of them having a relationship that needs to be hidden can add an element of excitement and tension. Another theme might be the power dynamics between them, as both are strong shinobi, and how that plays out in an intimate context.