At a young age, Sasuke had vowed to become an avenger, to kill the man who had ruined his life. He had trained and trained, striving to become stronger. He had distanced himself from everyone, focusing only on his goal.
But, despite his best efforts, the Uchiha found himself growing attached to his comrades. He fought against the bonds, trying to sever them before they formed, but it was to late; they had become his friends, his precious people, a strange sort of makeshift family.
Months later, before he left to join Orochimaru, he made another life changing vow. He promised himself he would cut off all his bonds and consume himself in the hatred he needed to become stronger.
He spent his time in Orochimaru's company hardly thinking of or missing his old life. Sometimes, he doubted it had ever existed, wondering if it had been some wishful dream.
Two and a half years later, a reminder of his past confronted him.
Haruno Sakura.
Fighting her should have been easy; she was the weakest member of their team, the one who always had to be protected. But something in Sasuke refused to hurt her. A tiny corner of his heart still viewed her as the defenseless comrade he needed to protect.
However, as he fought her, it became quite clear that she had changed greatly during his absence. She was stronger now, angry and determined as she attacked him without holding back.
Sakura charged at him, fist ready to deliver a jaw-shattering punch. Sasuke moved away at the last second, watching her fist tear through a tree that could've been his head. This battle was wasting precious time, and he needed to end it quickly.
He summoned two large snakes, sending them slithering toward the female faster than she could blink. Soon, they had wrapped around her, pinning her tightly to a tree. She struggled against them, determined to keep fighting, but Sasuke could tell she knew her efforts were wasted.
As he approached her, Sakura shut her eyes and turned her head away, apparently predicting his next action. He cupped her chin in his hand, tilting it up toward his face. At his silent command, the snakes pulled tighter around her body. She gasped, eyes shooting open as the air was crushed from her lungs.
The short instant that her eyes were open was all Sasuke needed. With his Sharingan, he was able to send the kunoichi into a deep, genjutsu induced sleep.
The snake summons disappeared in a puff of smoke, and Sasuke caught Sakura's limp body against chest when she slumped forward. Kneeling, he gently rested her sleeping form against the tree. With a quiet farewell, he turned and left, trying to ignore the strange guilt he felt at hurting her.