First of all, what is "Fan Fiction"?
Fan Fiction is where you can post stories and poems. It's as simple as that!
An example
I saw a dark shape in the sea. It was huge and graceful. Suddenly, I realised it was Lugia. Then it jumped out of the water and started singing its magnificent song. Lugia's wings blotted out the sun. It stayed there for a few minutes and then dived back into the sea.
They can be as short or as long as possible.
I know this is a Q&A, but it could do with some spicing up.