One idea could be that Sting and Lucy are on a joint mission. They get lost in an ancient, magical forest. As they struggle to find their way out, they start to share their deepest fears and dreams, which brings them closer. Another could be a story where Lucy is in danger and Sting has to fight off a powerful dark guild to save her, and during this, he realizes his true feelings for her.
One idea could be a time - travel plot where Lucy, Rogue, and Sting are sent back in time to the founding of Fairy Tail. They have to navigate the early days of the guild while also trying to find a way back to their own time. Another could be a magic - swapping scenario, where they accidentally exchange their magical abilities and have to learn to use each other's magic to fight a new, powerful enemy.
Sting's personality can be developed by showing his softer side. Usually, he's seen as a tough fighter. But with Lucy, he might show more vulnerability. For example, he could open up about his past and the things he regrets. Lucy, on the other hand, can develop by becoming more adventurous. Sting's bold nature might inspire her to take more risks. Also, they could both develop their communication skills. Since they are from different guilds originally, they might have different ways of thinking, and through their relationship, they can learn to communicate better and understand each other's perspectives.
One possibility is that it's a fanfic set in an alternate universe where Sting has a special connection with Lucy. They might discover a new form of magic together. For example, Sting's white dragon slayer magic could combine with Lucy's celestial spirit magic in an unexpected way, leading to a whole new set of adventures.
One plot idea could be Sting and Lucy teaming up for a really difficult S - class mission. They start off not getting along well because of their different guilds' rivalries in the past. But as they face various challenges during the mission, like powerful dark mages and dangerous terrains, they gradually come to respect and care for each other. Eventually, they complete the mission successfully and form a strong friendship that could potentially turn into something more.
One idea could be exploring how the other members of Fairy Tail support Lucy during her pregnancy. For example, Natsu might be overprotective, always making sure she's safe on missions or just in general. Another could be Lucy writing in her diary about her hopes and fears for the future as a mother, while also reflecting on her adventures in Fairy Tail.
One plot idea could be that Flare and Lucy are forced to team up on a mission. They start off not getting along due to their past differences. But as they face challenges together, like fighting a powerful dark mage, they begin to understand each other. Flare might learn about Lucy's kindness and determination, and Lucy could see Flare's hidden insecurities. Eventually, they form a strong friendship that could potentially turn into something more.
One idea could be that Mira and Lucy team up for a really difficult S - Class quest. They face all kinds of magical creatures and obstacles along the way. Mira uses her demon form's powers in a creative way to protect Lucy, and Lucy discovers a new Celestial Spirit that helps them out.
Well, a great plot could be that the OC is a former enemy who has a change of heart. He was once part of a dark guild but realizes the error of his ways. Lucy is the first to see the potential for good in him. They start training together, and the OC discovers he has a special connection to Lucy's celestial spirits. Maybe he can communicate with them in a way that Lucy can't. This leads to them uncovering a mystery about the origin of celestial spirits. Another option is that the OC has the power to create portals to different dimensions. He accidentally pulls Lucy into a dangerous dimension. They have to rely on each other to find their way back, and in the process, their relationship blossoms.
Another plot idea is that Lucy, while on a mission, discovers a strange magical artifact that has a connection to Naruto's world. She accidentally activates it and it summons Naruto. Together, they have to figure out how to send Naruto back while also dealing with the chaos that the artifact's appearance has caused in the Fairy Tail guild. For example, it could be causing some of the guild members to have strange powers or behaviors similar to those in Naruto's world.
A possible plot could involve a dark magic that starts affecting Fiore. Lucy discovers some ancient texts about it, and she realizes she needs the help of Sting and Rogue. They go on a journey to find the source of this dark magic. Along the way, they encounter many enemies. Sting and Rogue use their Dragon Slayer magic to fight, while Lucy summons her Celestial Spirits. As they get closer to the source, they find out that one of their old enemies has returned and is using this dark magic to seek revenge. Together, they combine their powers to defeat the enemy and save Fiore.