One possible plot could be that Kid Lexa and Costia meet in a forest. Lexa, being young, is curious about Costia who might be from a different clan. They start off a bit wary of each other but then find common ground in their love for nature. They could exchange stories about their respective clans' traditions regarding the forest, like how Lexa's clan uses certain plants for medicine and Costia's clan believes the forest has spirits that protect them.
Perhaps Kid Lexa is on a journey when she meets Costia. Costia could be in some sort of trouble, like being chased by a wild animal. Lexa, with her brave nature even as a kid, helps Costia. In return, Costia shows Lexa a secret place in the forest, a hidden glade with a beautiful pond. They then become friends and vow to keep the glade a secret between them.
In a fanfiction scenario, Kid Lexa might meet Costia at a clan gathering. Lexa is intrigued by Costia's unique style of dressing which is different from her own clan. They start talking and find out they both have dreams of uniting all the clans in peace one day. They then decide to start small by sharing their ideas of peace with the younger members of their respective clans.
It could develop through shared experiences. Maybe they both get lost in a maze - like part of the forest together. During this time, they have to rely on each other's skills to find their way out. Lexa's tracking skills and Costia's knowledge of the stars for navigation combine. This experience cements their bond and they become closer friends, with Lexa starting to see Costia as a sister - like figure.
One possible plot could be that Clarke and Lexa face many challenges together as they anticipate the arrival of their baby. They might have to deal with the reactions of their respective communities. Some people could be against their relationship and the idea of them having a child, but they stand strong together and prove that their love can overcome all. They prepare a cozy home for the baby and start thinking about how to raise the child in a world full of both danger and hope.
One possible plot could be about how they adjust to parenthood in a post - apocalyptic world. Maybe they face challenges like finding proper resources for the baby, protecting it from threats in their dangerous environment. Their relationship could also evolve as they take on this new role together.
Perhaps the fanfiction could revolve around Seimei Aoyagi meeting someone from a different time or dimension. They would have to learn to communicate and understand each other's cultures. It could be a story of friendship and mutual discovery.
One possible plot could be that the protagonist is a new student in school and meets Leo, who is a bit of an outcast but has a hidden talent for art. They bond over their shared love for a certain artist and Leo starts to open up, leading to a deep friendship.
Well, it could be about the various American characters in Hetalia getting together for a big meeting. Maybe they discuss trade relations among themselves, like how the North American regions interact with those in South America in this fictional Hetalia world. They might also share cultural things, for example, different festivals or traditions that are unique to each part of the Americas in the Hetalia universe.
Perhaps in this fanfiction, Bella had the kid in unexpected circumstances. She might be trying to keep the identity of the father a secret from the kid and the town. As the kid grows up, he or she starts to ask questions, and Bella has to decide whether to tell the truth or keep the secret, which adds a lot of drama to the story.
Well, one possibility could be a crossover where Naruto somehow ends up in the world of Death the Kid. Maybe Naruto's chakra is mistaken for some kind of unique soul energy. And Death the Kid, being the perfectionist he is, might be intrigued by Naruto's unruly and yet powerful nature. They could team up to fight some common enemy that threatens both their worlds.
One possible plot could be that Draco is turned into a kid by a misfired spell. His friends, who are used to his haughty self, now have to deal with a cute, innocent, and sometimes clueless kid - Draco. They might start to see a different side of him and form new bonds as they try to figure out how to turn him back.
Perhaps Kaito Kid kidnaps a fan by mistake. He was aiming for someone else who looked similar, and this fan is just an ordinary person who happened to be in the wrong place at the wrong time. The fan could be really scared at first, but then as they interact with Kaito Kid, they start to see a different side of him. Kaito Kid might then have to figure out how to let the fan go without getting caught himself.