Another possibility is that the main antagonist could be a corrupted member of Hinata's own clan. This person might be envious of Hinata's new power from the curse mark and tries to either take it for themselves or make sure Hinata fails in controlling it so that she brings shame to the clan. This would add an interesting layer of internal conflict within the clan as Hinata tries to deal with the curse mark and the threat from within.
It could be Orochimaru. He is known for his experiments with curse marks, and he might see Hinata as an interesting subject to study or use for his own evil plans.
Well, it could be about Hinata struggling with the new power and the negative effects of the curse mark. Maybe she has to learn to control it to avoid being consumed by its dark side.
Naruko is surely a main character. Additionally, there might be a mentor figure who helps her understand and control the curse mark. And perhaps there are antagonists, like those who want to take advantage of her situation or those who simply oppose her because of the mark.
Sakura is the central figure here. However, depending on the direction of the fanfiction, there could be new characters introduced. Maybe an old sage or a mysterious healer who claims to know about the curse mark. But the mainstay characters from the Naruto universe such as Kakashi Sensei could also be involved, guiding Sakura through this difficult time and helping her understand what the curse mark means and how to handle it.
She might gain new and unpredictable powers. The curse mark could potentially enhance her strength in combat, like giving her more chakra or new jutsu abilities. However, it could also come with a price, such as being influenced by dark forces.
Well, without actually reading it, it could be about Naruko's journey after getting the curse mark. Maybe she has to struggle with the power it gives and the negative effects it has on her. She might face challenges from those who fear or want to use her new power.
I'm not sure specifically as there could be many different takes on it. But generally, it might involve Sakura getting a curse mark which could lead to her facing new challenges, perhaps having to deal with dark powers within her, and it could change her relationships with other characters as they might view her differently or she might have to struggle to control this new aspect of herself.
It could be Neji. Even though they are family, Neji has been quite tough on Hinata in the past. His overbearing nature and the way he has sometimes looked down on Hinata could be the final straw that makes her snap.
There could be Naruto. Since he's Sakura's friend, he would likely be involved, trying to help her deal with the curse mark. He might use his own powers and experiences to support her.
Another option is a group of anti - magic fanatics. They view Percy's wings as an abomination because they are a result of magic. They hunt Percy down, believing that by getting rid of him and his wings, they are protecting the world from the 'evils' of magic.
It could still be Hawk Moth. Since Nathalie has been working with him, getting a Miraculous might make her a threat to his plans, so he could turn against her and become the main antagonist.