One common plot element could be their journey together. Maybe they are on a Pokémon adventure and during that, they develop a closer relationship which is the 'doing it' part in a more emotional or romantic sense, like sharing important moments or helping each other in battles.
I'm not sure about specific 'ash and may doing it fanfiction' as there are a vast number of fanfictions out there. However, you can try looking on popular fanfiction websites like FanFiction.net or Archive of Our Own. Search for 'Ash and May' and browse through the results to find ones that might interest you.
One possible fanfiction could be about Ash's adventures in Hoenn during the month of May. Maybe he discovers a new Pokémon species that is only active during this time of the year. He could be traveling with his usual companions and facing challenges specific to the Hoenn region.
Obviously, Ash and Misty are the main characters. Ash is a determined Pokémon trainer with a big heart for Pokémon. Misty, on the other hand, is a strong - willed girl who is also very knowledgeable about water - type Pokémon. In the fanfiction, their interactions and adventures together are usually the central focus.
It could be a rival trainer. Rival trainers are often very competitive in the Pokémon world. Maybe this rival is jealous of Ash and May's progress and decides to betray them to slow them down. They might spread false rumors about Ash and May, causing other trainers to be distrustful of them.
Often, these fanfictions will take the characters out of their normal settings. For example, they might end up in a different time period or a strange new land. This allows for a lot of creativity in the storylines. And the character development of May and Ash is usually a big part of it, showing how they grow and change throughout the story.
Yes, there might be. Fanfiction covers a wide range of scenarios and relationships, so it's possible that someone has written a story where May cheats on Ash. You can try searching on popular fanfiction websites.
A possible fanfiction plot could be that Ash, Serena, and May are invited to a mysterious island full of unknown Pokemon. They have to work together to survive and discover the secrets of the island. Ash's leadership, Serena's ability to communicate with Pokemon, and May's quick decision - making skills would be crucial.
One way is to focus on their friendship. For example, write about how they support each other during Pokémon battles. They can exchange tips on training Pokémon or strategies for winning competitions.
Ash could get angry. He has a strong sense of justice, and he might feel that May has violated their friendship. He could challenge her, not in a violent way, but more in a way to get an explanation and to try to make her see the error of her ways. He would likely be determined to show her that what she did was wrong.