One idea could be that Gemini takes on a new form that no one in Fairy Tail has ever seen before. This new form could have unique powers that they use to help the guild in a difficult battle against a powerful dark guild.
A cool plot could be that Gemini starts to develop emotions and a sense of self that is different from their normal role as celestial spirits. This causes some chaos in Fairy Tail as they don't know how to deal with a celestial spirit that is acting so 'human'. They might struggle with their loyalty to Lucy while also trying to explore their newfound individuality.
One idea could be a new character arriving at Fairy Hills and having to adapt to the unique living situation. They could face challenges like getting along with the different personalities of the Fairy Tail mages living there.
Gemini might also be intrigued by the different magical concepts explored in Fairy Tail fanfiction. The original series has a rich magical world, and fanfictions can expand on it even further. Some fanfictions might introduce new types of magic or combine existing ones in innovative ways. This creativity in the magical realm could catch Gemini's attention as it shows the limitless possibilities of the Fairy Tail universe.
One idea could be that Luffy joins the Fairy Tail guild and his rubber powers amaze everyone. He might participate in a guild - wide competition and use his unique abilities to win in unexpected ways. For example, stretching to reach far - off targets or bouncing around the arena to dodge attacks.
Maybe a mermaid in Fairy Tail fanfiction is cursed. Instead of having a beautiful voice like in traditional mermaid tales, she has a voice that causes chaos when she sings. The Fairy Tail wizards have to find a way to break the curse without sacrificing her powers. They could go on a journey to find a special artifact that can reverse the curse.
Perhaps in the fanfiction, there is a traveling burger - making wizard who comes to the Fairy Tail guild. This wizard has the ability to infuse emotions into burgers. So, a happy burger might make the eater feel extremely joyful, while a sad burger could bring out melancholy. The Fairy Tail members are intrigued by this concept and start to explore how these emotion - filled burgers could be used in their daily lives and in battles.
One idea could be a character from Fairy Tail having to box against a powerful magical opponent where their regular magic is restricted, so they rely solely on boxing skills. For example, Natsu could be in a situation where his fire magic doesn't work, and he has to use his brute strength and newly learned boxing moves to win the fight.
One idea could be a marriage between Natsu and Lucy. They could have a big, magical wedding in Magnolia where all their guild mates are involved. Maybe they face some kind of pre - wedding chaos like an enemy trying to disrupt the preparations but they overcome it together.
Well, a plot could revolve around a robot that has the ability to copy magic. It joins Fairy Tail to learn more about different types of magic, but some of the guild members are suspicious of it. As it tries to prove itself, it gets involved in a big conflict against an enemy who wants to use its magic - copying ability for evil. Also, there could be a story where a Fairy Tail mage creates a robotic sidekick. They go on adventures together, and the robot has unique abilities that complement the mage's magic, like being able to analyze an opponent's weaknesses quickly.
Another plot could be Aries traveling back in time. She could end up in a time when the Fairy Tail guild was first founded and interact with the founders. This would give her a chance to see how the guild has evolved and also allow her to contribute to the early days of the guild in some unexpected ways, like using her knowledge of future events to prevent a disaster that could have ended the guild before it really began.
Maybe there could be a big competition at the highschool, like a magical sports event. Different characters from Fairy Tail would form teams and compete, with rivalries and friendships being tested. For example, Natsu's team against Gray's team, and there could be some comical moments as well as intense battles.