Since lemon fanfics are inappropriate, we should focus on their general characteristics from the official story. Asta is highly determined and energetic, always striving hard despite his lack of magic initially. Yuno, on the other hand, is more calm and has a natural talent for magic. They both have a strong bond as rivals and friends.
Harry Potter himself is a likely candidate. Given his heroic nature and the need to constantly fight against dark forces, an Akuma no Mi could be a great addition to his arsenal of skills. It would give him new ways to protect his friends and defeat his enemies.
Noelle could be a great addition. Her water magic is quite powerful and she has a complex relationship with both Asta and Yuno. She could be a source of both support and conflict in the fanfic. Another good character is Luck. His lightning magic and his rather unpredictable nature can add a lot of action and excitement to the story.
Asta would likely bring a new level of determination to the Crimson Lions. His never - give - up attitude could inspire the team members during tough battles.
Sasuke. If Sasuke had an Akuma no Mi power, like the Goro Goro no Mi (Rumble - Rumble Fruit), it would make him even more formidable. He could use lightning - based attacks from his ninjutsu in combination with the electrical powers of the fruit. His already brooding and powerful character would become even more complex and dangerous.
Well, the Akuma origin story could be related to ancient curses. Maybe it was a result of a forbidden ritual gone wrong. In certain tales, Akuma is seen as a manifestation of the darkest human emotions. It gains its power from fear, anger, and hatred, and over time, it has evolved into a terrifying force that preys on the weak and the vulnerable.
I'm not sure if there is a specific fanfic exactly like that. There are so many Naruto fanfics out there, and while some might involve Naruto having an interest in Akuma in some creative crossovers, it would take some serious searching through fanfic platforms to find one.
Well, akumas typically have a back story related to a source of evil or a corrupting influence. It could start with a character who has some sort of inner turmoil or a tragic past. This internal struggle makes them vulnerable to the influence that turns them into an akuma. For example, if a character has lost a loved one and is filled with grief and anger, that might be the trigger for the akuma transformation, leading to a whole new set of actions and a role in the story as an antagonist.
Another place is FanFiction.net. There are some really good and unique 'Akuma no Riddle' fanfics there. Just use the search bar and type in 'Akuma no Riddle' to find relevant stories.
One great 'Akuma no Riddle Fanfiction' is 'The Unspoken Bond'. It delves deep into the complex relationships between the characters. The author does an amazing job of exploring the emotional depth that the original series only hinted at.