One idea could be a story where Pit and Viridi have to team up to save the world from a new, powerful enemy that neither could defeat alone. Maybe this enemy is a corrupted ancient deity that is spreading chaos and destruction.
The relationship could be developed through shared dreams. For instance, they both start having strange dreams about a mysterious place that seems to be in danger. As they try to figure out the meaning of these dreams together, they grow closer. Pit might start to understand Viridi's deep connection to nature better through this experience, and Viridi might see Pit as more than just a fighter for the heavens.
One common theme is the exploration of their relationship, whether it's a deep friendship, a brotherly bond or a complex rivalry. Another theme is their growth as characters, like how they become stronger together.
There's a fanfiction called 'Pit and Dark Pit: United Front'. In this story, they face a powerful common enemy and their bond grows stronger as a result. It's really exciting to read how they work in tandem. Also, 'The Dark to His Light' is a good one which focuses on the contrast and harmony between them.
Adventure - based themes are also popular. Writers might create new quests or battles for Pit and Palutena to go through together, which in turn strengthens their bond. This could involve them facing new and powerful enemies that they have to overcome with their combined skills and trust in each other. For example, they might have to journey to a far - off land to retrieve a powerful artifact that is crucial for saving their world. Along the way, their relationship blossoms.
You can try fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Kid Icarus Uprising Pit x Palutena' on their search bars, and you'll likely find a bunch of fanfictions related to this pairing.
There's also 'Dark Pit's Redemption' where he tries to make amends for his past actions. It has some great character development and an interesting plot that keeps you hooked. In this fanfiction, the author explores different sides of Dark Pit that we don't often see in the original game. It's really worth checking out if you're a fan of the character.
One possible fanfiction could be about Pit from Kid Icarus encountering a dragon in a world where Transformers (TF) also exist. Maybe the dragon has some sort of connection to the technology of the Transformers. For example, it could be a mechanical dragon that Pit has to fight or team up with depending on the plot.
In a fanfiction, Medusa could capture Pit and instead of killing him immediately, she tries to corrupt him. She might use her powers to show Pit false visions of a world where the gods have failed everyone. Pit would then have to resist her influence and find a way to escape.