The antagonist could be a dark force that has corrupted the snakes. In the fanfiction, this dark force might be trying to use the snakes to harm Sakura. It could be an ancient evil that has been awakened and sees Sakura as a threat to its plans. So it uses the snakes, which were originally neutral or even friendly, to try and get rid of her.
One possibility is that the snakes are under a spell. They wrap around Sakura because she has a certain energy or power that attracts them. In the fanfiction, this could lead to Sakura having to figure out why the snakes are drawn to her and how to break the spell on them. It could involve her using her medical ninjutsu skills or her inner strength that she has developed over time.
In fanfiction, Sasuke's shadow snakes wrapping Sakura could lead to a very tense situation. It might be a part of a battle scenario where Sasuke is initially hostile towards Sakura. Or perhaps it's a miscommunication, and the snakes are used to restrain her before Sasuke realizes his mistake. It could also be a dark - themed fanfiction where Sasuke has turned evil and the snakes are a symbol of his new, menacing power over Sakura.
She could also be shocked and a bit scared at first. But then, her medical ninja training kicks in. She might analyze the situation quickly, looking for weaknesses in the snakes' grip. Maybe she tries to use her knowledge of the human body (since she's a medic) to find a way to make the snakes loosen their hold, like targeting pressure points on the snakes if they have any.
Sakura might have a hidden jutsu or power that she has not yet fully explored. In this dire situation, she could tap into this unknown ability to break free from the snakes. For example, she could have some latent chakra - based power that she discovers can repel or dissolve the snakes binding her.
Sakura could also be more composed in her reaction. Given her growth as a character, she might try to reason with Sasuke first. She could say things like 'Sasuke, I know you must have a reason for this. Let's talk about it.' However, if Sasuke doesn't respond or seems hostile, she may start to feel betrayed. She might then use her medical ninjutsu knowledge to try to find a weakness in the snakes or in Sasuke's technique that is keeping her tied up. She could also start thinking about how she can turn the situation around and make Sasuke see reason.
In this fanfiction, it could be that Sasuke has lost his mind due to some traumatic event. He ties Sakura with snakes because he sees her as a symbol of the world he wants to reject. The snakes could represent the chaos and danger that he now associates with her. Meanwhile, Sakura might be in shock at first, but then she starts to analyze the situation. She realizes that Sasuke is not in his right mind and tries to use her medical knowledge and ninja skills to not only free herself but also to heal Sasuke's broken psyche.
One possible plot could be that Sasuke, with his snake - related powers or abilities, restrains Sakura in a non - harmful way as part of a training exercise. He might be trying to teach her how to break free from unexpected restraints in battle situations. For example, he could use his snakes to hold her arms gently while she tries to use her medical ninjutsu skills and strength to escape.
In a fanfiction, the shadow snakes of Kabuto could be enchanted or mutated in some way. Sakura, with her trusty fan, might be on a mission to study or cure these strange snakes. This could lead to an adventure where she has to face Kabuto, who is protective of his shadowy creations.
The plot could involve Kabuto sending his shadow snakes to steal a valuable scroll from Sakura. Sakura uses her fan to defend the scroll. The fan could have some hidden abilities that she discovers during the fight, like the ability to create illusions that make the snakes attack each other.