Naruto Shippuden Movie 5: Blood Prison: Ryuzetsu

She's an kunoichi Aubu from the Grass Flower Group of Kusagakure and was childhood friends with Mui's son, Muku due to the two wanted to restore their village to its former glory before Muku was being sacrificed as a failed attempt to open the Box of Ultimate Bliss, leaving only his green scarf. She disguised to a boy in order to infiltrate Hozuki Castle to stop Mui from reopening the Box of Ultimate Bliss and to avenge Muku's death. She had a quiet, stoic personality but opened up after meeting with Naruto and refused to let him die.