Sasuke's character could develop in terms of his ninja skills. If Itachi kidnaps him, perhaps he will be forced to train in a new and harsher environment. This could make him stronger not only physically but also mentally. He might learn new jutsu or improve his existing ones at a much faster rate. Also, his understanding of the Uchiha clan's history and power could deepen during this time, which would shape his identity as an Uchiha.
During the ordeal of being kidnapped by Itachi, Sasuke might develop a greater sense of self - reliance. Without his usual support system from Konoha, he has to rely on his own wits and abilities. This could lead to him becoming more confident in his own decisions. Moreover, if Itachi reveals some family secrets during the kidnapping, Sasuke could develop a more complex view of his family and his place in it. He may no longer see things in simple black - and - white terms of revenge, but rather strive to uphold the true values of the Uchiha clan.
In many fanfictions, Sasuke starts as a character full of anger and a thirst for revenge. But in the context of a relationship with Itachi, he begins to soften. He starts to see Itachi in a different light, beyond just the person who killed their clan. Itachi, on the other hand, is often portrayed as a complex figure with many secrets. In these fanfictions, his love for Sasuke makes him more vulnerable and human. For example, in some stories, he reveals his true motives to Sasuke, which changes their dynamic.
Sasuke's character could develop in terms of his loyalty. By saving Sakura from Itachi, he shows his loyalty to his friends and comrades. He is no longer just the revenge - driven Sasuke. He has grown to care about others' safety.
Sasuke might develop more patience. Since Itachi is younger in this fanfiction, Sasuke has to be more understanding. He can't be as impulsive as he usually is. For example, he might have to learn to soothe Itachi when he's scared or upset, which helps Sasuke grow into a more empathetic person.
Sasuke would likely be enraged. Naruto is his rival and also, in a way, his friend. He would immediately set out to find Naruto and confront Itachi. Sasuke has a strong sense of pride and would not let his brother get away with this.
Sasuke could also be confused. He has always had a mix of emotions towards Itachi, including love, hate, and envy. Being kidnapped by him would add another layer of confusion. He might wonder if Itachi has some new plan or if he's finally going to reveal some long - hidden truth. So, he might hold back on his full - fledged resistance and wait to see what Itachi has to say.
Sasuke might become more protective. Since Sakura is a princess, he feels a stronger sense of duty to keep her safe, which changes his usually aloof demeanor.
Sasuke's character can also develop through his interactions in the new time period. If he travels to a time where he meets his family again, he could learn the value of family and love that he lost in his original timeline. He might become more empathetic and less isolated. He could also gain new skills or knowledge from the different time, which would further shape his character.
His understanding of relationships might grow. Through his interactions with Sakura, Sasuke could learn about compromise, forgiveness, and unconditional love. For example, he might learn to forgive himself for his past mistakes and understand that Sakura loves him despite all that.
Sasuke's character often develops in terms of his loyalty. By saving Naruto, he shows that his loyalty to their friendship is growing stronger. He may start to question his previous lone - wolf attitude.
The kidnapped character could use their own hidden jutsu skills to break free. For example, if they have a teleportation jutsu they've been hiding, they could use it when Sasuke is distracted. Another way is to appeal to Sasuke's emotions. If they can remind him of his better nature or a past event that made him more empathetic, he might let them go.