Maybe the author wants to build up the tension. In many fanfics, delaying the first kiss can create a sense of anticipation. Ash might be focused on other things like his Pokemon training and adventures, so his romantic relationships take a backseat for now.
It depends on the direction the fanfic writer wants to take. If the fanfic is more about friendship and Pokemon battles, then he might not. But if it has a strong romantic sub - plot, he probably will. For example, if the story is building towards a resolution where Ash realizes his true feelings for Misty, a kiss could be a natural conclusion to that arc.
There are many fanfics out there that involve Ash, Misty, and the idea of a kiss, along with Paul. Some fanfics might focus on Ash and Misty's relationship development over time, with Paul being a rival or a side character that adds some drama. For example, in some fanfics, Paul's presence might make Ash realize his true feelings for Misty, leading to a romantic kiss scene. These fanfics can be found on various fanfiction websites.
Mainly, Ash is a central figure as he is in the Pokémon anime. He's the one whose actions and relationships are often focused on. Misty, his long - time friend and now the one involved in the kiss with him, is also a main character. And Paul, who has his own way of doing things in the Pokémon - training world. His leaving after Ash and Misty's kiss is what makes him an important part of this fanfic.
One possible plot could be that Ash and Misty share a kiss, which is witnessed by Paul. Paul, feeling out of place or perhaps jealous, decides to leave. After Paul leaves, Ash and Misty might have to deal with the aftermath of their kiss. They could face mixed reactions from their friends, and they themselves might be confused about their feelings towards each other. Maybe they start to explore a romantic relationship further.
In some fanfics, Misty might be portrayed as betraying Ash for power. For example, if there is a powerful trainer who offers Misty a chance to become an even greater trainer, but at the cost of leaving Ash behind. She could be tempted by the allure of advanced training techniques or rare Pokémon that this new opportunity presents.
One good fanfic could be 'The Unspoken Feelings' which beautifully portrays Ash and Misty's relationship with Paul as an interfering factor at times. It has a great build - up to their kiss scene. Another one is 'Rivalry and Romance' where Paul's rivalry with Ash is intertwined with Ash and Misty's budding romance, leading to a very emotional kiss. You can find these on popular fanfiction platforms like FanFiction.net.
It's doubtful that it's a popular fanfic. Popular fanfics usually tend to build on the positive aspects of the source material, like the friendship or adventure between characters. A concept where Ash kills Misty is so out of the ordinary and negative that it probably doesn't appeal to a wide audience. However, there might be a small niche of readers who are interested in very dark and alternative fanfics, but overall it's not likely to be popular.
Well, a fanfic about Ash, Misty and Charizard in Kalos could be really exciting. Maybe it could start with Ash arriving in Kalos with Charizard, and then Misty comes to visit. They could explore the unique Pokémon in Kalos together, and Charizard might have some interesting battles against the local strong Pokémon. It would be a great story to show their friendship and adventures in a new region.
One idea could be that Ash and Misty visit Unova for a Pokemon tournament. They meet new friends and face new challenges together. Misty could use her water - type Pokemon in creative ways against the Unova Pokemon's unique types.