It could also be a situation where an alternate version of Harry is created, a Harry who has been raised in a much harsher and more unforgiving environment. This Harry might have developed a different moral compass and in a moment of extreme stress or anger, lashes out at his relatives. This could be set in a 'what - if' scenario where Dumbledore never intervened in Harry's life and he was left to the mercy of the Dursleys without any protection or guidance.
One possible plotline could be that Harry is under the influence of a dark spell or dark magic artifact which makes him lose control and kill his relatives. Maybe it's a cursed object that he unknowingly comes into contact with, and it twists his mind, leading to this tragic event.
Well, it depends on how it's written. If it's written in a very graphic and violent way, then it's definitely disturbing. However, if the author is trying to explore some deeper themes like the psychological breakdown of a character or the consequences of extreme abuse, it might be less disturbing in the sense that it has a more thought - provoking aspect rather than just shock value.
Well, perhaps in a fanfic, Malfoy could be involved in a plot to destroy Hogwarts and Harry, in a fit of rage and desperation to protect his school and friends, ends up killing Malfoy. Or it could be that Malfoy is working with a new, extremely dangerous dark force, and Harry's attempts to stop him go too far and result in Malfoy's death. There could also be a scenario where Malfoy accidentally gets caught in the crossfire of a battle between Harry and another dark entity, and Harry is blamed for his death.
In this kind of fanfiction, perhaps Vernon is driven by jealousy. He sees how much attention Harry gets, even if it's often negative attention within the household. This jealousy festers until he decides to take drastic action. It could also be related to some long - held family secrets or grudges that are finally brought to the surface, leading Vernon to try and kill Harry.
One possible plotline could be that Naruto is under some sort of dark magic or mind control. Maybe an enemy has found a way to manipulate his actions and make him turn on his friends. Another could be a situation where Naruto is tricked into believing his friends are actually enemies in disguise. For example, if there was a powerful genjutsu that made him see his friends as threats to the village.
In some fanfictions, it could be a case of a powerful curse that forces Harry to act against his will. The curse might be placed on him by a powerful dark wizard who wants to create chaos in the wizarding world. Draco is just an unfortunate victim of this curse as Harry, unable to control himself, kills Draco. This then sets off a chain of events where Harry has to deal with the guilt and the consequences of his actions.
One possible plotline could be that Harry discovers he has a half - brother he never knew about. Maybe his father had a relationship before he met Harry's mother, and this new character enters Harry's life. They initially have some conflicts due to jealousy or differences in upbringing, but over time, they come to love and support each other.
One possible plotline could be Harry feeling extremely isolated and trying to find new friends outside of his usual circle. Maybe he starts to focus more on his studies and discovers new magical abilities on his own.
Perhaps in the fanfiction, Naruto is tricked into believing his clan is a threat to the village. So, in an attempt to protect Konoha, he takes drastic measures and kills them. It could also be that a powerful and evil entity takes over Naruto's body, and using his strength, murders the clan while Naruto is powerless to stop it from within.
Well, it could be that he has lost all hope. In the fanfiction world, if the situation becomes so dire that he sees no way out for himself or the people he loves. For example, if Voldemort manages to gain complete control and Harry Potter thinks his sacrifice by taking his own life might be the ultimate solution to break Voldemort's power. He might also be suffering from post - traumatic stress after all the battles and losses, leading him to this extreme decision.
Well, it could be a story where Harry is tricked into believing that Muggles are responsible for some great harm to his loved ones in the wizarding world. So, in his rage and misdirected sense of justice, he starts targeting Muggles. But this is a very un - Harry - like behavior as the real Harry is all about protecting the innocent, whether they are wizards or Muggles.