Well, it might be a fan - made story within a particular fandom. Maybe 'him' is a character who has done something wrong but Sakura, for some reason like compassion or a deeper understanding of the situation, decides to let him escape. It could involve elements of adventure, mystery, or even some sort of emotional turmoil depending on the overall context of the fanfiction.
One possible reason could be that he has some crucial information that Sakura needs. Maybe he knows secrets about their world or a powerful enemy, and if he escapes, that knowledge will be lost.
Since I haven't read it, I can't be certain, but from the title it seems Sakura and 'him' are likely the main characters. Sakura is the one making the decision to let 'him' escape.
It's also possible that he is a mysterious character who has some sort of connection to Sakura's past or her powers. His presence might trigger something in Sakura, and she can't let him go until she figures out that connection.
Perhaps Naruto realizes that forcing Sasuke to stay would only create more resentment. By letting him escape, he hopes that Sasuke will have time to think and eventually return willingly. In the fanfiction, it could also be that Naruto has some sort of premonition that Sasuke's escape is necessary for a greater good in the future, like saving the village or the ninja world in a different way than if he were held back.
She could also pretend to cooperate with Orochimaru at first. Gain his trust a little bit and then when he least expects it, make her move. Maybe she could ask Orochimaru for some tools or access to certain areas under the pretense of helping him with his work, but in reality, she is setting up her escape.
Well, it's not really ethical. Sasuke should be more upfront and find other ways to escape rather than using Sakura like that. Sakura trusts Sasuke and for him to seduce her just for his own gain, like escaping, is wrong. Fanfiction might play with these concepts in different ways, but overall it's a behavior that doesn't sit right. It also doesn't fit well with Sasuke's character development in the original story where he is trying to become more than just a self - centered person.
Sakura could use her medical ninjutsu skills to create a distraction. For instance, she might make it seem like she's poisoned herself, causing Sasuke (or whoever is involved in the kidnapping) to get closer, and then she could attack and escape.
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.
Well, without more specific information, it's hard to say exactly what the 'let him go real story' is about. It could be a story of self - discovery where the main character realizes that holding on to 'him' is preventing their own growth. Maybe 'him' is a negative influence, and the story is about the journey of finding the strength to let go, which could involve facing fears, dealing with emotions, and ultimately moving forward in life.
She might be shocked at first. Sakura is used to Naruto being more passive when it comes to her hitting him, so when he suddenly stops her, it could catch her off - guard.