What could be the story of Naruto and Erza's daughter in fanfiction?

One possible reason could be a misunderstanding. Erza might misunderstand Naruto's intentions. For instance, if Naruto is on a mission that involves some secretive actions, Erza could misinterpret them as something malicious and decide to betray him.

It could be that Erza has a special connection to the Nine - Tailed Fox because of her relation to Naruto. She might be able to communicate with it in some way. Her personality could be a blend of Naruto's goofiness and Erza's seriousness. In terms of her story arc, she could start off as a young girl trying to prove herself in a world full of powerful ninjas and mages. As she grows, she discovers more about her heritage and uses it to protect those she loves and the world at large.

Perhaps there is a prophecy that only Naruto and Erza together can fulfill. They start off as strangers but as they journey to fulfill the prophecy, they discover that they have a lot in common. They both have a strong sense of justice and a will to protect their friends. As they face numerous enemies and obstacles, their friendship turns into a deep respect for each other's abilities, and they become a formidable team.

If Erza was Naruto's daughter in fanfiction, her relationship with Sasuke could be interesting. Maybe Sasuke would see her as a reminder of Naruto and be both protective and a bit standoffish at first. With Sakura, she could be like a little sister figure, and Sakura would help her with her medical ninjutsu skills if she wanted to learn. And with Kakashi, he could be her mentor, just like he was to Naruto, guiding her in the ways of the ninja.

She might have Naruto's blue eyes and Erza's red hair. Her face could have a combination of their features, with Naruto's cheeky smile and Erza's strong jawline.

They could have adventures where they combine their skills. Naruto could use his ninja techniques like shadow clones, and Erza could use her different armors and magic. For example, they might fight against a powerful enemy that is a threat to both their worlds. Naruto's clones could distract the enemy while Erza changes into her strongest armor to deliver a powerful blow.

Naruto might gain the ability to use magic weapons like Erza. Since he's a quick learner, he could master the use of different magical swords or armors. He could infuse his chakra into these weapons to make them even more powerful. For instance, a sword that can cut through any material when combined with his chakra and also has the ability to cast magic spells.

In this fanfiction, perhaps Erza is found by Naruto when she's injured. Naruto takes her back to Konoha. Since he has a big heart, he wants to give her a home. As she recovers, they start to bond. Erza might be amazed by the chakra system and Naruto could be intrigued by her magic. They could then go on adventures together, with Naruto protecting her like a father figure at first, and later they become equal partners.

One possible plot could be that Naruto, while on a mission in a strange dimension, meets Erza. They initially clash due to their different ways of handling things but gradually fall in love. Naruto then decides to stay in Erza's world and they get married, facing challenges from both their friends and enemies who are skeptical of their union.

One possible plot could be that Naruto somehow gets transported to the Fairy Tail world before Erza is born. He then meets Erza's mother and gets involved in her life. Eventually, he becomes a father figure to Erza as she grows up, teaching her some of his ninja skills and values from the Naruto universe.