Tsukado

Tsukado is a master swordsmen of an unnamed clan who had a vendetta against a man that killed a relative of his, Shikazo. Tsukado was chosen with the task of avenging him by the killing the man who killed him, Katazu. He failed 34 times to defeat him. One day, Team 7 meets Tsukado and seeing his poor revenge skills, Naruto decides to train him. Though his lessons were unusual, he managed to get the upper hand in his next fight with the killer. Naruto stops the fight after noticing Katazu's sword wasn't even sharpened, saying he couldn't possibly kill his relative. He says that it was his twin brother, Kageki who killed his relative but it was an accident. Since then, he has been taking his brother's identity. The Kanabun Gang, who were profiting off their fight, try to get the two to fight again but with the help of Team 7 manage to chase them out of town. Tsukado is shown to be able to use chakra flow when using his sword.

(source: Narutopedia)