Sakura would probably be furious at first. She is a strong - willed character. She might start yelling at Sasuke, demanding an explanation right away.
Another way she could react is by using her medical ninjutsu skills. She might try to find a way to free herself secretly while still talking to Sasuke, in case he has been influenced by an enemy. She would be on high alert and ready to defend herself if needed, all while trying to understand Sasuke's motives.
Sakura would probably be initially shocked and angry. She has always cared about Sasuke, and this betrayal would hit her hard. But she is also a strong - willed ninja. So, she would quickly gather her wits and start looking for ways to escape. She might try to use her knowledge of Sasuke's fighting style against him if she gets the chance.
Sakura would be over the moon. She would blush deeply and look at Sasuke with so much love in her eyes. She might be at a loss for words for a moment, but then she would find her voice and tell Sasuke that she has been waiting for this moment her whole life. She would also feel a sense of pride that Sasuke has chosen her, after all they have been through. And she would immediately start thinking about how to share the good news with their friends, especially Naruto, who has been like a brother to her and has also been a part of their journey.
Sakura might be initially frustrated. She's used to Sasuke being in control, so seeing him drunk could be a bit of a shock. But then she'd probably feel a sense of protectiveness and try to sober him up.
Sakura's reaction would depend on how the author writes her character development. If she's become more confident in herself, she might approach Sasuke with a more assertive attitude. She could tell him that she's not the same girl he left behind. However, she'd still have that underlying love for him. She might also be worried about how the village will accept Sasuke's return and how it will affect her standing in Konoha. So her reaction would be a complex blend of personal feelings and concerns for the village.
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.
Another reaction could be that Sakura tries to follow Sasuke. She believes that she can change his mind or that she can be of help to him. She might leave her own responsibilities behind for a while to chase after him, thinking that their bond is strong enough to overcome whatever is making Sasuke leave.
Sakura would probably be initially very angry. She has strong feelings for Sasuke, but kidnapping is a very extreme act. So she would likely fight back, using her medical ninjutsu skills and combat abilities to try and escape.
In some fanfictions, Sakura's reaction could be more complex. She might be hurt not just physically but also emotionally. This could lead her to question her relationship with Sasuke and might cause her to make some big decisions, like whether to continue trying to reach out to him or to cut him off completely.
On the other hand, there would be fans who would welcome it. Maybe they never liked the pairing in the first place or they think it adds an interesting twist to the story. They could start exploring new relationships for both Sasuke and Sakura in their own fan - created stories.
Sakura might be heartbroken at first. She has always been in love with Sasuke and to find out he's cheating would shatter her world. She could become withdrawn and focus more on her medical ninjutsu as a way to cope.