Ron Weasley, with his loyalty and sometimes impulsive nature, could also end up with an Akuma no Mi. He could use the power to prove himself and stand by his friends in a more powerful way. His growth as a character could be really interesting as he learns to control and utilize the new power within the context of the Harry Potter world.
Hermione Granger could also be a good fit. Her intelligence and thirst for knowledge would make her eager to study and master the powers of an Akuma no Mi. She might be able to find unique ways to use the power in combination with her existing magical knowledge.
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.
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.
One interesting concept could be the combination of the magical world of Harry Potter with the unique powers of the Akuma no Mi from One Piece. For example, a character might use a Devil Fruit power in a wizarding duel, creating a whole new dynamic of combat. It could also involve characters from Harry Potter having to adapt to the rules and limitations of the Akuma no Mi powers in their own universe.
Harry Potter himself is often a popular character in these fanfictions. Writers might explore how he would react to Akuma - related threats. Hermione is also popular as she could use her intelligence to understand and combat Akuma - like phenomena. Another popular character could be Draco Malfoy, perhaps being involved in Akuma - influenced dark magic plots.
One interesting concept could be how the powers of the Akuma no Mi would interact with the ninja abilities in Naruto. For example, if a character had a Logia - type Akuma no Mi, like the Mera Mera no Mi (Flame - Flame Fruit), they could use it in combination with fire - based ninjutsu to create more powerful attacks. Another concept might be the clash of values between the One Piece world where the Akuma no Mi exist and the Naruto world. In the Naruto world, they value things like teamwork and honor in a different way compared to the pirates in One Piece.
One interesting idea could be the fusion of Akuma's powers with the magic in Harry Potter. For example, an Akuma - like curse being cast within Hogwarts. Another might be characters from Harry Potter having to face off against Akuma - inspired villains. It could also be about a character from the Akuma world attending Hogwarts and how they interact with the students there.
Luka is another character that shows up a lot. His calm and understanding nature, along with his relationship with Marinette, provides a contrast to the more chaotic aspects of akuma attacks. His love for Marinette, whether it's unrequited or reciprocated, can be a central part of the fanfiction. He might also play a role in helping Marinette deal with her feelings for Adrien while akumas are causing trouble in their lives.
Since I don't have specific information about this 'akuma to love story', it's difficult to say. But it's likely that there is a character who is an 'akuma' or has some connection to the 'akuma' concept, and then a love interest. Maybe there's a brave hero - type character who falls in love with the 'akuma' against all odds.
As we don't have details about this particular 'akuma shoujo web novel', the main characters could include the akuma shoujo, of course. There may be a mentor figure who helps her understand and control her powers. And perhaps there are antagonists, such as other devil - related beings who want to use her for their own evil purposes or those who simply want to destroy her because they see her as a threat to the normal order.
Since I don't have specific information about this visual novel, I can't name the exact main characters. But generally in visual novels, the main characters are often those who drive the story forward, whether they are protagonists with special abilities or ordinary people caught up in extraordinary situations.
There could also be an antagonist or a group of antagonists. They would be the ones creating obstacles for the main character and other protagonists. Their actions and motives would be crucial to the development of the mystery and the story as a whole. They might be trying to prevent the riddle from being solved for their own gain or to maintain some sort of power or control within the world of the light novel.