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The Hyuuga clan were one of the founding noble families of Leaf village. The clan itself is said to be the ancestors of the Uchiha clan who possess the bloodline of the Sharingan eye. Each clan member possess the "Byakugan" or "White Eye." When the "Byakugan" is activated, the clan member gains an extra-sensory perception, which gives them penetrating sight and telescopic vision. This allows them to see the internal chakra circulation system in other beings. This vision also grants the member a near 360° view of their surroundings. The higher the skill of the clan member, the further the distance from which they can sense incoming attacks. Unfortunately the vision does have a weakness, a small blindspot that extends outwards from their upper back.

The clan uses this ability in conjunction with their own chakra creating the Juuken (gentle fist) fighting style. By focusing the chakra to their finger tips, they can press the tenketsu or chakra pressure points of their opponents body. When the finger nears the tenketsu the chakra is forced out, collasping the targetted tenketsu for a period of time. The tenketsu serve as the connectors and exit points for the chakra pathways. So when they are stopped by the Hyuuga clan member, the ninja greatly loses his or her ability to utilize their chakra for jutsu.

These great powers lead to internal strife within the family. Because the eye grants such a unique and powerful ability, the clan became possessive and over-protective of it. Seeing only the main family as worthy users and inheritors of the eye, the heads of the clan began to place restrictions on those branch family members not in power. What resulted were two Hyuuga lines, the powerful main family who would represent the line, and the branch family who were directed to protect the main family and bear the cursed seal.

The cursed seal is placed on the foreheads of branch family members. It serves as a means to protect the secrets of the Hyuuga Byakugan eye. If the branch family member was to ever betray the main family or be killed in battle, the seal would be activated to destroy the body's secrets. Thus forcing the branch family to further bow to the will of the main family.