Another possible betrayer could be Dumbledore in some darker fanfictions. He might have a hidden agenda all along. He could be using Harry as a pawn in a much larger and more sinister game. And when Harry starts to figure things out and goes against Dumbledore's plans, Dumbledore betrays him to keep his own plans on track.
Yes, there might be. Fanfiction platforms are filled with a vast variety of stories. You can start by checking major fanfic sites like Archive of Our Own or Fanfiction.net. Just search for the relevant keywords and you may find what you're looking for.
Well, it could be about Harry Potter experiencing a sense of betrayal within the context of the 'light' side in the wizarding world. Maybe the so - called good characters or forces that are supposed to represent the light, like the Order of the Phoenix or Dumbledore, do something that makes Harry feel let down or betrayed. It could involve secrets being kept from him that he later discovers and feels were a form of betrayal.
The idea of 'Harry Potter Betrayed' in 2018 fanfiction could also be related to a betrayal of Harry's ideals. Some new character or even an old one could act in a way that goes against what Harry stands for, such as using dark magic when Harry firmly believes in the power of love and light magic. This would not only be a personal betrayal for Harry but also a threat to the world he has been trying to protect.
Another possibility is that it could be a new character introduced in the fanfiction. This new character could be someone who gains Harry's trust quickly but then betrays him for personal gain or because they are secretly working for an enemy. For example, a new student at Hogwarts who seems friendly at first but is actually a spy for a dark wizard.
Another instance could be Hermione betraying Harry in fanfiction. Suppose she falls in love with someone who is against Harry, like a pure - blood supremacist in a different version of the wizarding world. Her love for this person makes her go against Harry, which is a huge betrayal considering their close friendship in the original story.
In regular fanfiction, we might see stories that are more in line with the positive aspects of the 'Harry Potter' world, like new adventures at Hogwarts or additional spells and magic. But 'Harry Potter betrayed' slash fanfiction delves into the negative emotions associated with betrayal. It could involve characters acting out of character in order to create a scenario where Harry or other main characters are betrayed. This can be a very different experience for the reader compared to the more traditional fanfics.
It could be Ron. Maybe he starts to feel that Harry has changed too much after the war and is no longer the friend he once knew. He might be influenced by outside forces or his own insecurities. Another possibility is Hermione. If she gets too involved in the new Ministry politics and starts to believe that Harry's actions are not in line with the new wizarding order, she could turn on him.
It might be popular because it allows fans to take control of the story. In the official Harry Potter stories, there are set relationships and storylines. But in fanfiction, especially this type, fans can create their own scenarios where they can make the characters face unexpected and difficult situations like betrayal within a harem - like setting. This gives a sense of novelty and freedom to the fans who want to explore the Harry Potter world in a different way.
I'm not sure of specific examples off the top of my head. But in general, in such fanfiction, it might involve Harry being betrayed by those in his so - called harem, perhaps by lies or broken trust. For instance, a character he trusted might turn out to be working for the dark side and use their relationship to get information on him.