One possible fanfiction could be about Sun and Lillie going on an adventure together in the Alola region. They might discover a new and rare Pokemon that only appears during a certain lunar phase. Sun could use his skills as a trainer to protect Lillie from any potential danger, and in the process, their relationship could grow deeper.
One great 'Moon Knight x Reader Fanfic' is 'Midnight Encounters'. It has a really interesting plot where the reader character stumbles upon Moon Knight during one of his nightly patrols in a rather spooky alley. The chemistry between the two is built up slowly and realistically, making it a very engaging read.
A simple plot could be that Sun and Lillie are on a quest to find a special Z - Crystal. They face many obstacles along the way, such as difficult terrain and other trainers. Their relationship develops as they support each other through these challenges.
There are 'sun x moon fanfic' that focus on their symbolic relationship. In some, the sun represents passion and energy, and the moon represents tranquility. A story could be about how they balance each other out. The sun's fiery nature is tamed by the moon's gentle presence, creating a harmonious universe within the story's universe.
The relationship between Moon Knight and the reader should be developed organically. It can't be rushed. In some fics, they meet and fall in love immediately, which isn't very believable. A good fic will show the progression from strangers to something more, with all the bumps and hesitations along the way.
Tuxedo Mask is one of the most frequently paired characters. His mysterious and charming nature makes him an appealing love interest for the reader. Also, Sailor Moon herself is often paired with the reader in a more platonic or sisterly way, with the two of them sharing a strong bond. And sometimes, Sailor Mars is paired with the reader, especially in fanfictions that focus on a more fiery and passionate relationship.
Well, in Sailor Moon x Reader fanfiction, a common trope is the transformation. The reader often discovers their own powers and goes through a cool transformation sequence, similar to the Sailor Scouts. Also, the 'Secret Identity' trope is popular. The reader might have a secret identity that they have to keep from the other characters while still being part of the group. And of course, the 'Power Struggle' trope, where the reader has to deal with their newfound powers and the responsibilities that come with them.
Realistically, their relationship might start with a simple friendship. Sun helps Lillie become more confident around Pokemon, especially if she was initially a bit scared. As time passes, they start to rely on each other not just in Pokemon - related matters, but also in personal situations. For instance, when Lillie has a problem with her family, Sun is there to support her, and vice versa. Small gestures like sharing food or taking care of each other when sick can also contribute to a deeper relationship.
One interesting plot idea could be that Sun and Lillie go on a journey to discover a new type of Pokemon that has been rumored to exist in a hidden part of Alola. Another could be that they have to team up to save Lillie's mother from some sort of dark force. Maybe they also find a time - traveling Pokemon that takes them back to the past of Alola, and they learn about the origin of some of the local traditions.
A possible plot is that the Akatsuki from Naruto are after some powerful and rare Pokemon in the Alola region. They believe these Pokemon can give them ultimate power. The Alola trainers, along with Naruto and his team, have to stop them. Naruto could bond with a Pikachu that has some unique abilities, similar to how he bonded with Kurama. They face off against the Akatsuki in epic battles where both ninja techniques and Pokemon moves are used.