One common theme is forbidden love. Since Sasuke's sister is from the Uchiha clan and Naruto is an outsider in a way, their relationship often goes against the norms and expectations of their respective clans and the ninja society as a whole.
First, give her a distinct personality. If Naruto is all about determination and Sasuke is brooding, she could be the calm and wise one. Then, give her a backstory. Maybe she was separated from Sasuke at a young age and grew up in a different part of the ninja world. This would shape her view of things. Another way is to show her relationships. For example, how she interacts with Naruto's friends like Sakura and Kakashi. This will help to flesh out her character more.
There's also 'Sister of the Uchiha and the Jinchuriki'. In this fanfiction, the author delves deep into how Naruto and Sasuke's sister interact in the context of the complex political and social situations within the ninja villages. Their relationship is a blend of friendship, mutual respect, and a hint of something more. It's a great read for those who like exploring different character dynamics in the Naruto universe.
One great Naruto x Sasuke (in a fanfiction context not in a inappropriate way) fanfiction could be those that focus on their deep bond. For example, some might explore how they support each other during difficult missions. They could rewrite key moments in the series from a different perspective, like the Valley of the End battle, but instead of fighting out of hatred, they fight to protect each other from an outside threat.
One popular place to search for Sasuke x Naruto fanfiction is Archive of Our Own (AO3). There are tons of well - written stories there that explore different aspects of their relationship, from friendship - based ones with a lot of angst to more romantic interpretations. Another option could be FanFiction.net, which also has a large collection of fan - created stories about these two characters.
She could have a special connection to an ancient ninja art. Naruto wants to learn from her to become stronger and Sasuke is intrigued as well. This causes some competition between them at first. But then they realize that they can all benefit from her knowledge. Also, her existence could stir up old family secrets. Maybe she has a connection to the Uchiha clan that Sasuke doesn't know about, and this revelation could change his perception of his family and his relationship with Naruto.
In some fanfictions, they interact more like true siblings. Naruto might be overly protective of Sasuke, and Sasuke could be more open with his feelings towards Naruto. For example, Sasuke might share his insecurities about his clan's past with Naruto more freely.
Normal fanfiction usually focuses on elements like their friendship, rivalry, or their roles in the Naruto universe. For example, it might explore how they influence each other's growth as ninjas. However, 'Naruto x Sasuke hard lemon fanfiction' often contains inappropriate and adult - themed content that is not in line with the general spirit of the Naruto series.
If Sasuke's sister was in the picture, Naruto and Sasuke's relationship might soften more quickly. Naruto would see another side of Sasuke through his sister. He might also feel more of a connection to Sasuke's family. Sasuke, on the other hand, would see Naruto's genuine care for his sister, which could make him trust Naruto more.
Sure. There are fanfictions that center around their teamwork in battles. They might describe how Naruto and Sasuke strategize together, using their unique abilities to overcome enemies. This type of fanfiction is more about their partnership and growth as ninjas rather than any inappropriate or overly intense themes.