A plot could revolve around Pikachu getting sick and Lillie using her knowledge of Pokémon care to nurse it back to health. During this time, they develop a deep friendship. Then, they notice some strange behavior in other Pokémon around them. Together, they start to investigate and find out that there is a pollution source affecting the Pokémon. Lillie and Pikachu then try to find a way to clean up the pollution and restore the health of the Pokémon in the area. This would show their caring and adventurous sides.
One idea could be that Pikachu wakes up in a strange part of the mystery dungeon with no memory of how it got there. It has to team up with other Pokemon it meets along the way, like a Charmander and a Squirtle, to figure out the mystery of the dungeon and also find a way to get back home.
Another plot could be that the reader is lost in a strange part of the Pokemon world and Pikachu is the one who finds them and leads them to safety. Along the way, they become great friends and share many adventures. This could involve exploring new areas, meeting different Pokemon species, and learning about the secrets of the Pokemon world.
One idea could be that the female Pikachu has unique electric powers that no other Pikachu has. She could go on a journey to discover the origin of these powers, facing various challenges along the way, like battles with powerful Pokemon and difficult terrains.
A great idea for a Pokemon Detective Pikachu fanfic could be to set it in a different region. For example, a region that is mostly covered in ice. Pikachu and Tim would have to adapt to the new environment and the different types of Pokemon there. They could be investigating a series of disappearances of ice - type Pokemon. Maybe there's a secret underground lair where a powerful but misunderstood Pokemon is hiding and Pikachu has to use his detective skills to uncover the truth and save the day.
One idea could be that Lillie discovers a mysterious lemon - shaped Pokemon that has unique powers. Maybe it can heal other Pokemon with its lemon - scented aura. Another plot could involve Lillie using lemons to create a special treat for her Pokemon, which then gives them a temporary boost in battle. A third idea is that a lemon - themed villain tries to steal all the yellow - colored Pokemon in the Pokemon world, and Lillie has to stop them.
Maybe in the fanfiction, Lillie gets transported to an alternate dimension where the rules of Pokemon battles are different. She has to quickly adapt and learn these new rules with the help of her Pokemon. It could involve her meeting different versions of her friends from Pokemon Moon in this strange new world.
One idea could be a story where Lillie discovers a hidden power within herself during an adventure with the protagonist in Pokemon Sun. Maybe she can communicate with a rare and powerful Pokemon that no one else can. This could lead to a series of events where they have to protect this Pokemon from an evil organization.
Their relationship can be developed through shared experiences. For example, when they encounter a difficult Pokémon battle together, Pikachu can protect Lillie, and Lillie can in turn use her skills to support Pikachu. This mutual reliance will strengthen their bond.
One idea could be a story where Pikachu gets separated from the trainer in an unknown and dangerous area, like the mysterious depths of Viridian Forest. It has to find its way back while making new Pokemon friends and facing challenges from wild Pokemon.
One idea could be that Pikachu suddenly loses its electric powers and Ash has to find a way to help it regain them. This could involve a journey to a mysterious place that is said to have the power to restore Pokemon abilities.