A character like Severus Snape could be an interesting choice. He already has that mysterious and somewhat dark aura about him. Transforming him into a demon butler would add an extra layer of complexity to his character, and his relationship with Harry could be re - imagined in a whole new way.
Bellatrix Lestrange could also be a candidate. Although she is a villain in the original series, as a demon butler, she could have a more nuanced backstory. Maybe she was forced into the service of a demon, and now she has to serve Harry Potter for some reason. It would be a very different take on her character.
I think Sir Ian McKellen would be a great choice. He has that air of elegance and mystery about him. His acting skills are top - notch and he could bring a lot of depth to the role of the butler.
Dobby could be a great butler. He was always eager to serve Harry and was very loyal. His knowledge of the Malfoy manor and other wizarding households could be useful. And his unique brand of magic, like his ability to apparate in and out of places where other wizards couldn't, would add an interesting dynamic to the story.
Dobby could be a great character as a butler in fanfiction. He already has a strong loyalty to Harry and his self - sacrificing nature would make him an excellent butler. He could use his house - elf magic to keep Harry's living quarters clean and protected.
One implication could be the confusion of the two fan bases. Fans of Harry Potter might be put off by seeing their beloved characters in a context that doesn't align with the original series. Similarly, Black Butler fans may not appreciate the distortion of their favorite story.
In the world of fanfiction, there are often very creative and out - of - the - box ideas. However, 'harry potter is a demon black butler fanfiction' seems more like a misappropriation. Harry Potter is about a boy wizard's journey through a magical school and his fight against the dark lord. Black Butler is about a young noble and his demon butler. Mixing them in this way just doesn't fit well.
One idea could be that the demon butler is secretly protecting Harry from a new, unknown dark force in Hogwarts. He uses his demonic powers to sense danger before it arrives.
The butler could be a protector. He might use his skills, like combat skills or knowledge of ninjutsu, to keep Naruto safe from various threats, whether it's rogue ninjas or political schemes.
Another option could be Michael Caine. He has that classic British charm and elegance that would be perfect for a butler role. He could bring a sense of humor and warmth to the character, while still being able to handle the more serious and magical aspects of the story.
One interesting character could be a self - made female demon who defied the normal ways of becoming a demon in the fanfiction. She might have her own unique powers and a very different view of the demon world compared to the traditional demons. Another could be a female demon who has a soft spot for a particular human, which is quite against the nature of demons in general. This internal conflict makes her character really interesting.
One great 'Black Butler Demon Reaper Fanfiction' is 'The Reaper's Bond'. It delves deep into the relationship between the demon and the reaper in a very interesting way. The story has a unique plot that shows how they might interact beyond what we see in the original series. The characters are well - developed and their dialogues are engaging.