BEFORE ECONTRA
- Speculation -
Sakura was born to civilian parents in Konohagakure ("Konoha", "Hidden Leaf Village", "The Leaf", or "The Village Hidden in the Leaves," depending on the language, formality, and dialect involved). As with all children in Konoha, she was enrolled in the Ninja Academy, but chose to continue at the Academy when civilian children were given the option for a normal education.
- Canon -
Sakura has an unusually large forehead which her naturally bright pink hair tended to enhance. Children, being a cruel breed, teased her mercilessly for it, making Sakura introvert to the point she grew her hair out to cover her face. This drew attention to it, leading others to tease her even more than before and leading to Sakura hiding out by herslf. Then along came Ino, who gave her some great advice, a ribbon to hold her hair back, and a dose of confidence in herself.
With more confidence in herself, she began to make friends, and shined in her classes where intelligence and theory dominated. The practical she was average on, though she did work hard at this. She even got her first crush.
Sakura wasn't sure how it happened. All the other girls liked him, but she didn't see the appeal in Uchiha Sasuke. If anything, his haughty ways annoyed her, but she was nice to him since all the other girls liked him and she still remembered what it was like to be all alone. Slowly, she began to notice things - like how her top scores on the exams were challenged only by him, or how skilled he was at the practical without relying on his bloodline technique - the Sharingan. Unlike the other boys in her classes, he kept himself rather neat and he knew how to take care of himself. She realized Sasuke wasn't just a pretty face and a little asking around led her to find out the bare bones of what had happened to his family. She found that he was surprisingly strong, that he didn't want pity, that he could survive.
These observations made her respect him, respect grew into admiration, and admiration grew into affection. Before she knew it, she had a crush on Sasuke herself and hid it for a few months before she decided to "go for it." Sakura knew someone like Sasuke would only date a girl who was capable. She just didn't know in what ways. Unlike the other girls who were crushing on him, she didn't think he would appreciate her dumbing herself down for him.
She did what she could to catch his attention, she thought the fishnet that was popular amongst ninja was tacky, but her usual black outfits were drab, so she started waring red to catch his eye. She heard Sasuke liked girls with long hair, so she grew hers to nearly waist length and took care of it as best she could. She worked hard to finish out at the Academy, as it was uncommon for children who weren't from the Clans to be able to keep up and graduate. If she wound up on a team with him, she wasn't going to slow him down.
Unfortunately, Sakura was also a child with her first crush. Whenever Sasuke was around, she went from her normal now-confident self into a clingy girl who would only pay attention to Sasuke to the point where she was annoying and would wind up driving him away.
She got competitive about it.
Unlike the other girls, who vied for his attention behind one another's backs, she outright declared to her best friend she had a crush on him and that they were now rivals. The two silently competed for Sasuke's attention from that day forward.
Sakura graduated and was placed on the same team as Sasuke, to her delight. Unfortunately, she was also placed with Konoha's Number One Knucklehead - Uzumaki Naruto. They're teacher was Hatake Kakashi, the Copy Ninja and Konoha's Number One Procrastinator. Both annoyed Sakura to no end.
At the start of their ninja training, Sakura focused mostly on catching Sasuke's attention, but slowly she began to move from seeing him as a goal to seeing him as a person and her feelings began to change from crush into love. What type of love, Sakura wasn't sure, since it was the same kind of care she'd started feeling for Naruto.
Eventually, Team Seven took the Chunin Exams to become the next rank of ninja. Sakura was one of the few test takers able to answer the test questions without cheating (the point of the test was to discretely cheat without getting caught). During the second phase (survival), her team was attacked by the followers of Orochimaru who were targeting Sasuke. Sasuke and Naruto were knocked out and Sakura was forced to fend for herself to protect the two of them instead of the other way around as had been the norm beforehand. In a moment of desperation, she wound up having to cut her hair and literally bite her opponent until Ino and her team came to save the day.
Sasuke, who had been given the cursed seal by Orochimaru, awoke shortly after and went into a fit of blind rage due to this. Sakura was able to dissuade him from continuing his rampage and the group made it to the check point.During the next phase for one-on-one matches, Sakura and Ino were pitted against one another and the match wound up with a double knockout.
The two wound up becoming close friends again afterwards.
Konoha wound up being invaded shortly after by Orochimaru. During the battle, Sakura winds up nearly being suffocated to death by a currently-insane Gaara of the Sand after protecting Sasuke from being caught. Naruto manages to save her. Unfortunately, the Hokage, Sarutobi, winds up killed in a battle against Orochimaru and Sasuke ultimately winds up defecting to the Otogakure - Hidden Sound Village.
As he's leaving, Sakura pleads with Sasuke to either stay in Konoha or take her with him - even going so far as to confess her feelings to him. His response was to knock her out and leave her there. She never heard him tell her "thank you," much less wonder what he was thanking her for.
She made Naruto promise to bring Sasuke back when he left with the squad assigned to bring him back. A task that, unfortunately, he failed in. Touched by his determination when he sees her again that no mater what, he would bring Sasuke back, Sakura decided to try to better herself and promises that the next time, they would bring Sasuke back together. She then asked the new Hokage, the Lady Tsunade, if she can become her apprentice, a request to which Tsunade agrees.
- Disasterpiece -
However, when news reached her about Sasuke and Orochimaru's supposed death three years later, Sakura withdrew into herself. For a time, she blamed Naruto for not bringing him back and herself for not trying harder to go with him when he left.
Sakura joined Naruto and other members of the Konoha elite in hunting down and killing various members of Akatsuki, acting as the team's healer and losing several dear friends along the way. When not on missions, she worked under Tsunade and became involved in the politics of Konoha, working to ensure Naruto wouldn't have any challenges to become Hokage from a political standpoint. Later, she uncovered a plot by a subdivision of ANBU called ROOT that Sasuke may in fact be alive and were planning on assassinating him. Through a member named Sai, Sakura managed to gain information on where Sasuke may have been and managed to get the group to give them time to at least find and attempt to reason with Sasuke before they would assassinate him.
Before she could tell Naruto this information, the two of them found themselves facing Madara Uchiha. The battle was long and hard and Sakura had just finished healing one of the other members of their team when she noticed Madara unleashing a powerful Jutsu on Naruto. Not even bothering to think, she ran forward, placing herself between Naruto and the blast and then . . .
DURING ECONTRA
. . . in great pain and miraculously healed enough during the transfer so her injuries were not immediately fatal, she found herself in Econtra.
POST-ECONTRA
. . . Sakura is killed by Madara's Jutsu, leaving not even a trace of her body behind.