The Oath of Pain.

The Oath of Pain is the eighth chapter/episode of The Life of a Kunoichi Shinobi.

Synopsis
With Kakashi captured in Zabuza's  Water Prison Technique, Kristin, Naruto, Sasuke, and Sakura are forced to defend against Zabuza's attacks. Kakashi tells them to run. Naruto instinctively moves to flee, but, feeling the pain in his hand, remembers his oath of pain. He decides to fight to save Kakashi and keep Tazuna alive. He tells Sasuke and Kristin that he has a plan.

Naruto uses his Shadow Clone Technique to completely surround Zabuza's clone, who, with one swing of his sword, causes most of Naruto's clones to scatter and disappear. The remaining Naruto passes a Fuma Shuriken to Sasuke, who senses his teammate's plan.

Sasuke uses Shadow Shuriken Technique, throwing two shurikens at Zabuza. Zabuza easily catches the first shuriken but only dodges the second at the last moment. Once past Zabuza, the second shuriken transforms back into Kristin who had disguised herself to trick the superior ninja. Naruto had one of his shadow clones transform into Kristin, then the jutsu broke. Kristin throws a kunai at Zabuza that forces him to stop his jutsu, freeing Kakashi from his prison.

Trivia

 * When Kristin was attacked by Zabuza, she gripped her left side; which is where her demon seal is located. This foreshadows the arrival of Helena