Kakoi

is a member of the Konoha Barrier Team.

Background
In the anime, the Third Hokage reported to Kakashi that someone had been slipping through Konoha's Sensing Barrier. Kakoi reported that the possibilities were that there was a traitor who had knowledge of how not to trigger it, of that someone had a jutsu that could break through it. He showed Kakashi reports where the barrier was on high alert, around the self-governing Uchiha district. Hiruzen tasked Kakashi with installing a sensing barrier there without linking back to the Anbu.

Personality
Kakoi is a conscientious and dutiful person who is concerned about the welfare of the village.

Appearance
Kakoi has shoulder-length brown hair and unique markings under his eye. He wears a high-collared white tunic and white hat.

Abilities
By using Water Release, Kakoi was able to erect an immense Sensing Barrier with the help of others, which allowed him to monitor the situation in Konohagakure.

Pain's Assault
He was first seen monitoring the village's Sensing Water Sphere when Pain's assault on Konoha begins and mobilised the first responders.

Trivia

 * When Kakoi's name is written as, it means "enclosure".
 * In the anime, Kakoi is shown to be part of the Konoha Barrier Team around the time of the Uchiha Clan Downfall, depicted as approximately the same age as during Pain's Assault over a decade later.