In the fanfic, Lucy could develop a more adventurous side. Since Rogue is often involved in more dangerous and shadowy things, she might be drawn into that world and have to adapt. For Rogue, being around Lucy could make him more in touch with the positive aspects of the magical world. He might start to question his own darker tendencies and strive to be a better person. This could lead to him making different choices in battles and in his relationships with others.
Lucy may develop a deeper understanding of the darker side of magic through Rogue. This could make her more well - rounded as a mage. She might also become more assertive in her relationships within Fairy Tail. Rogue's character could be transformed by Lucy's positive influence. He could start to trust others more easily, especially Lucy. Their relationship could be a catalyst for both of their characters to grow in ways that they wouldn't have in the original Fairy Tail story.
One possible plot could be that Rogue somehow gets transported to Lucy's world and they have to figure out how to get him back. During this time, they start to understand each other better. Lucy might learn about Rogue's past and his struggles, and Rogue could see the kindness and strength in Lucy. They could develop a friendship or something more as they face various challenges in the Fairy Tail world.
For Lucy, you could develop her character by showing her growing more confident in her magic. Maybe she starts to experiment with new ways to summon her Celestial Spirits or combines their powers in unique ways. With Sting, you can explore his past more deeply. Show how his experiences as a Dragon Slayer have shaped his personality, and have him face some internal conflicts related to his power and identity. As for Rogue, you could develop his relationship with his shadow. Maybe he discovers new abilities within his shadow magic. Also, in the fanfiction, put them all in situations that force them to interact and grow together. For example, a mission where they have to protect a village from a powerful dark mage.
Naruto would likely be curious about the magic in the Fairy Tail world. He might see Lucy's celestial spirit magic as similar to his own summoning jutsu in a way. As for Lemon, if she has a friendly personality, Naruto would probably befriend her quickly. Fairy Tail characters, on the other hand, would be intrigued by Naruto's ninja abilities. They might ask him to show off some of his cool jutsus. Lucy could potentially teach Naruto about the different types of magic in Fairy Tail, while Lemon could offer her own unique perspective on things.
The story could develop in many ways. Maybe the SI - as - Lucy would start to modernize the Fairy Tail guild a bit. She could introduce new ideas based on her previous life's knowledge. For example, better ways of communication within the guild or new training methods.
Their relationship could start with mutual suspicion. Lucy is a member of Fairy Tail, and Midnight is from a different, often opposing group. But as they interact more, they might find common interests. For instance, they could both be interested in a particular type of magic theory. This shared interest could be the starting point of them gradually warming up to each other.
The story could focus on their journey to find a new place to belong. They might meet new allies along the way who have different values and magic abilities, which would add new elements to the story. For instance, they could encounter a group of mages who use music as their form of magic.
For Lucy, you could explore her celestial spirit powers more deeply. Maybe she discovers a new and rare spirit that has a special connection to Rogue or Sting's magic. For Rogue, his relationship with his shadow could be further developed. He might learn to use his shadow in new ways, and Lucy and Sting could play a role in that discovery. For Sting, his leadership skills could be tested and improved. They could be put in a situation where Sting has to lead a group that includes Lucy and Rogue, and he has to make tough decisions.
A fanfiction could show their friendship developing through their shared love for Fairy Tail. They all have different reasons for loving the guild. Lucy loves the sense of family, Natsu loves the adventure, and Gray loves the chance to better himself. They start to realize that they have more in common than they thought. They begin to train together, help each other with personal problems, and before long, they have a strong, unbreakable friendship within the walls of Fairy Tail.
At first, it could be a relationship of mistrust. Lucy might be scared of Laughing Jack's appearance and his unpredictable behavior. But as they are forced to work together on various tasks or face common enemies, they start to understand each other better. For instance, Laughing Jack might show a protective side towards Lucy during a dangerous mission, which makes her see him in a new light.
Some characters like Natsu might be initially suspicious. He's always been competitive with Sting, so he might think they have some ulterior motives. But characters like Lucy would probably be more welcoming. She's always open - minded and would see it as an opportunity to make new friends. Happy would also be curious and might follow them around to see what they're up to.