She might love it for the expanded universes. Fanfic often takes the existing fictional world and expands it further.
One reason could be that she might be worried about Ash getting into dangerous battles. She cares deeply for him and the thought of him getting hurt scares her.
It might be that Ash has other priorities now. For example, real - life commitments such as work or study have taken up too much time, leaving no room for writing fanfic.
It could be that there is some misunderstanding between them. Say, Misty misinterprets something Ash does as him not caring about her anymore. Ash, being clueless about her misinterpretation, doesn't correct it in time. Then Misty distances herself from him, and Ash is left heartbroken when he finally realizes what has happened.
One reason could be that both Ash and Gary have only just realized their feelings for Misty at the party. They might have been suppressing their emotions before. Ash could see Misty in a new light, perhaps because of how she looks or behaves at the party. Gary, too, might suddenly feel a strong attraction and not want to lose her to Ash.
One reason could be that fun novels often spread positive values like friendship and courage in an engaging way. God might love how these values are promoted through fictional stories. For example, many fun adventure novels show characters working together and being brave in the face of difficulties.
It could be that she has a penchant for the extraordinary. Black roses are not as commonly seen as other colors, so her love for them might be a way of expressing her individuality and her love for things that are a bit different from the norm.
One reason could be for the sake of adventure. If he's immortal, he can go on countless adventures without the worry of dying. It allows the story to be more continuous and expansive.
Well, it could be that Harry is dealing with extreme emotional pain and feels hopeless. The consequence might be a huge shock to the wizarding world and a deep sense of loss for his friends.
One possible reason could be a lack of time. Maybe Ash has become too busy with other aspects of life, like work or studies, and can't find the time to write fanfiction anymore.
One popular 'ash loves misty fanfic' could be 'A Journey of Hearts'. It beautifully depicts their relationship growth. Another might be 'The Bond Beyond Pokemon' which focuses on their emotional connection. And 'Ash and Misty's Unseen Adventure' also has an interesting take on their story.