One way could be through his magical abilities. For instance, if in the fanfiction he has a new spell or power that is directly related to death, like the ability to instantly end a life or transfer a soul. Another way could be his role in the story. He might be the cause of death for many characters, either intentionally or unintentionally.
Maybe the fanfiction alters his backstory. If he was born from some dark magic related to death or has a hidden heritage that links him to death. His actions throughout the story could also be death - centered. He could be on a quest to end certain things or people, and his presence is always associated with the end of life. He could also have a connection to deathly artifacts that make him the embodiment of death in the fanfic.
It could mean that in this fanfiction, Harry Potter is seen as a symbol or representation of death. Maybe the author has reimagined Harry's character in a way that he has a very close connection to death, like he might be a force that brings death in some way or is a physical manifestation of the concept of death within the fictional universe of the fanfic.
In some Harry Potter fanfiction, death might protect Harry in various ways. For example, it could be that the threat of death makes him more cautious and thus protected. His near - death experiences could also have awakened certain powers or abilities within him that act as a form of protection.
The magic in Harry Potter is taught in schools and has a whole community of wizards and witches who use it. Death Note's magic is more of a solitary power held by the user of the Death Note. In fanfiction, this contrast can create great storylines. Say, a young wizard in training stumbles upon the Death Note. He has to decide whether to rely on his learned magic from Hogwarts or the new and dangerous power of the Death Note. And his professors at Hogwarts would be completely clueless about how to deal with such a strange object.
Harry would likely develop a very different personality. He may be more solemn and less prone to the typical teenage angst that the original Harry had. Since he is raised by Death, he might be more in tune with the darker aspects of life and magic from a young age.
Yes, there are likely fanfictions out there with this concept. The 'Harry Potter' fandom is vast and creative, and many fans like to explore unique and alternative storylines. Some might imagine Harry having a special connection to the idea of 'Lord Death' in a fan - created narrative.
In some fanfictions, the 'Master of Death' concept from Harry Potter might be combined with Twilight elements in really creative ways. For example, the character who becomes the Master of Death could have abilities that interact with the vampire and werewolf lore in Twilight. They might use the power over death to, say, reverse the vampiric state or bring back a werewolf from the brink of death in the Twilight - Harry Potter crossover universe.
Death in Harry Potter fanfiction can also serve as a means of exploring the afterlife in the wizarding world. Writers might imagine different versions of what happens to a wizard's soul after death, whether it's a continuation of the journey in a different plane or a form of reincarnation within the magical realm. This adds a new dimension to the already rich world of Harry Potter.
The Death God in Harry Potter fanfiction could be a new, dark force. It may be introduced as an ancient entity that has been dormant for centuries and is now awakened. This entity could be in conflict with the existing magical order in Hogwarts and the wizarding world. It might target certain characters, like Harry, because of his connection to the prophecy and his power to defeat Voldemort. Fanfic writers may use this concept to explore themes of mortality, fate, and the limits of magic that were not fully explored in the original series.
They can be blended by having crossovers of characters. Imagine Harry Potter characters being resurrected in the Avengers universe. Harry could use his magic skills to help the Avengers in their battles. Or an Avenger could be sent to the Harry Potter world after a near - death experience and learn about their magic and how it relates to life after death. They could then bring back that knowledge to their own universe and apply it in a different way, like using it to bring back a fallen teammate in a more magical way rather than just through science - based means.
Well, in a fanfiction, the Spirit of Death could act as a link between the two worlds. In the Harry Potter series, death is a complex concept, and in Naruto, there's also the idea of death and the afterlife with the Shinigami. So, this spirit of death could be a sort of mediator. It could bring characters from Harry Potter like Harry himself or Hermione to the Naruto world to learn about their ways of dealing with death. Or it could take Naruto characters to Hogwarts to see how magic is used in relation to death. They could exchange knowledge and skills regarding death - related matters.