Kō Hyūga

is a shinobi of Konohagakure and a branch member of the Hyuga clan.

Invasion of Pain
He is the protector of Hinata when Pain attacked Konoha, because Hanabi and Hiashi Hyuga were on a mission. As Hinata tried to help Naruto, Kō called her back claiming that she would only be a burden to him. Later, he watched in horror as Hinata went ahead anyway. He was unable to restrain her due to a broken leg he had sustained in combat against Pain.

Byakugan
As a member of the Hyuga clan, Ko has the ability to use the Byakugan to his advantage. In the Invasion of Pain arc, he uses the Byakugan to see Naruto fighting Pain.