Another theme is the continuation of the adventure in a different way. As Pikachu ages, the nature of its adventures changes. It might become more of a mentor to younger Pokemon, passing on its knowledge and experiences. This shows that even though it's ageing, it still has an important role to play in the Pokemon world.
In some Pokemon fanfiction, Pikachu's ageing might be shown through physical changes like a slightly greying of its fur. This could symbolize the passage of time and the experiences it has had. For example, an older Pikachu might be a bit slower in battles but wiser in its strategies, having learned from countless encounters over the years.
Another theme is the overcoming of differences. For example, Pikachu might fall in love with a pokemon from a different type or nature. They then have to work through their differences to be together. This can involve things like different battle styles or living habits. It makes for an interesting story as they learn to accept and love each other despite their disparities.
Friendship is a very common theme. The unbreakable bond between Ash and Pikachu is often explored. Another theme is adventure, as they are always going on quests in the Pokemon world. Trust is also a big theme, as they rely on each other completely.
One common theme is the journey they go on together. They might face challenges in the Pokemon world and their love helps them overcome. Another could be how they discover their feelings for each other in the midst of their daily Pokemon lives.
Another common theme is self - discovery. Pikachu may start out not knowing its full potential, but through the experiences in the mystery dungeon, it learns more about itself. It might discover new abilities or learn more about its personality traits, like its courage or loyalty. This theme adds an interesting layer of character development to the fanfictions.
One common theme is friendship. Female Pikachu might form special friendships with other Pokemon, perhaps in a more emotional or nurturing way compared to the male counterpart. Another theme is her relationship with trainers, especially female trainers, and how they bond over shared experiences.
The concept of facing fears is a theme that can be explored. Ash may have fears about not being a good enough trainer, and Pikachu could have fears related to its own power or protecting Ash. Fanfictions can show how they overcome these fears together. Additionally, the theme of legacy could be present. Ash wants to be a great Pokemon master like his idols, and Pikachu is part of that journey. Their story could be seen as part of the greater Pokemon legacy, and fanfictions can play with this idea in different ways.
One common reason could be jealousy among other Pokemon. Some Pokemon might be jealous of Pikachu's closeness to Ash and its popularity. So, they might plot against it and end up killing it. Another reason could be a misunderstanding. For instance, a wild Pokemon might misinterpret Pikachu's actions as a threat and attack it fatally.
A common theme is friendship. Pikachu and Buneary are often shown as good friends, relying on each other. Another theme could be adventure, as they explore the Pokemon world together.
Growth is also a theme. Ash is constantly growing as a Pokémon trainer, and in fanfictions, this growth can be depicted in different ways. Maybe he learns new training techniques with Pikachu's help, or he overcomes personal fears that were holding him back in his journey.