Haku

Haku was born during a time when people with a kekkei genkai were feared. Because Haku's mother possessed such an ability, so too did
Haku. Once Haku's father learned of this he
rallied a small mob and had his wife
murdered. He would have done the same to
Haku, but Haku inadvertently killed both the
mob and his father via his kekkei genkai.
Orphaned, Haku wandered the country as a
beggar child until he was found by Zabuza Momochi. Zabuza took Haku in as a tool of battle and nothing more. For his part, Haku readily accepted this role due to the purpose it gave him, devoting his life to becoming the ultimate weapon for Zabuza. In time, Haku became fiercely protective of his master, so much so that he would not allow anyone to touch Zabuza. He looks so much like a girl that Naruto confuses him with a girl when they meet prior to their battle. In his devotion to Zabuza, Haku finds purpose in life only by being of use to Zabuza, and does whatever is asked of him to continue to give his own life meaning. When he is defeated by Naruto Uzumaki, Haku feels as though his reason for living is gone as he is no longer of use to his master. His moment of abandonment is short-lived, as he is soon able to give up his life to protect Zabuza from Kakashi Hatake's Lightning Blade.

 

Haku's kekkei genkai, Hyoton, allows him to mix wind and water to create ice. Haku's ice is reinforced by chakra, making normally effective methods of melting ice, namely fire, practically useless. Haku's signature attack with this ability is his Demonic Ice Mirrors, which creates any number of mirrors made of ice to trap opponents. Haku can freely merge with and move between these mirrors, allow him to attack opponents from multiple angles simultaneously. Haku is also skilled with senbon, and can incapacitate or kill a person with a single senbon. Despite these abilities, Haku dislikes needing to kill in his role as a tool, and avoids doing so whenever possible. When forced to face an opponent Haku does all that he can to avoid bringing them great harm, even putting them into a death-like state to prevent them from fighting further.