Hizashi Hyūga

was a jōnin of Konohagakure's Hyūga clan.

Background
Hizashi was born seconds after his twin brother, Hiashi. For this reason only however, Hiashi was made the successor to the Hyūga clans, whereas Hizashi was made a member of a Branch House. At some point in Hizashi's life, he was branded with the clan's curse seal that would ensure his lifelong service to the main branch and that would seal his Byakugan when he died. Hizashi was unhappy with this fate, but felt that there was nothing he could do and put up with it.

Hizashi eventually fathered a son, Neji. Several years after Neji's birth, Hiashi's daughter, Hinata, turned three. As was customary to do on the next heir's third birthday, Neji was given his own curse seal. Hizashi was upset that his son was being locked into the same fate that he was, and briefly put up with this as well. But as time went by, Neji's natural genius with the Hyūga clan's techniques became obvious to Hizashi. At the same time, Hinata was proving to be ill-suited as the Hyūga's next leader. Angry that Neji was being denied his full-potential because of his birth, Hizashi became more open with his disapproval of the Main House, eventually manifesting as killing intent. Sensing this, Hiashi activated Hizashi's curse seal as punishment, causing Hizashi great pain and giving Neji reason to doubt the Main House for the first time.

Some time later, in an event that would become known as the Hyūga Affair, Hiashi killed the Head Ninja of Kumogakure to save Hinata. Kumogakure demanded Hiashi's body as restitution; in reality, they wanted to obtain the secrets of the Byakugan. The Hyūga elders and Konoha's leadership proposed that Hizashi be used instead; as Hiashi's body double. In addition to protecting Hiashi - the Hyūga's leader - doing so would keep the Byakugan's secrets from being discovered. Hizashi agreed. When Hiashi tried to refuse, Hizashi disabled him with a single blow. He then explained that he was not doing this to preserve the Hyūga's structure, but to save the life of his brother, to prevent war, and to choose his own fate for the first time in his life. Before going to his death, Hizashi asked Hiashi to tell Neji of his reason for his decision, regretting that he had shown Neji his bitterness in life.

Appearance
Hizashi was a mirror image of his brother Hiashi with the exception of having been branded with the Hyūga Main Family's Juinjutsu on his forehead. He had long, black hair and featureless, white eyes — the latter trait shared by all members of his clan. During his lifetime, he was seen wearing several outfits. While not on duty, he wore a long-sleeved, loose-fitting kimono held closed by an obi, which seemed the common attire of the clan. While on duty, he wore a simple black outfit with mesh armour underneath, his black forehead protector, and an obi around his waist. After he assumed his brother's identity, he donned a similar outfit to him consisting of a simple, white kimono, held closed by a dark-coloured sash along with a brown, long-sleeved haori.

Abilities
Little is known about his overall abilities but from all indications, he was a talented shinobi. His prowess and renown was great enough that Kabuto Yakushi chose to reincarnate him during the Fourth Shinobi World War.

Byakugan
Being a Hyūga, Hizashi was born with the Byakugan, which granted him near 360° x-ray vision (with the exception of a small blind spot at the upper thoracic vertebrae), x-ray vision and the ability to see the chakra pathway system.

Taijutsu
Hizashi also excelled in chakra regulation and the standard Gentle Fist fighting style like other members of the Hyūga clan and was even skilled enough to completely immobilise his brother with just one strike. During the Fourth Shinobi World War, Hizashi was shown to be evenly matched with his brother, with neither seemingly gaining the upper hand. He was also noted to exceed his older brother with regards to strength. In the anime, he displayed that he also knew how to use the techniques of this Main House which are derived from the Gentle Fist Art, such as the Eight Trigrams Palms Revolving Heaven — repelling several enemy attacks with the normally exclusive technique.

Fourth Shinobi World War: Confrontation
In preparation for the Fourth Shinobi World War, Hizashi was reincarnated by Kabuto Yakushi to fight against the Allied Shinobi Forces, before being mobilised alongside Asuma Sarutobi and Dan Katō where upon being informed by Dan of their current situation, he questioned why this was happening. Relocated to the Land of Lightning's coast, Hizashi emerged from the sea amongst the White Zetsu Army with the others, before engaging the opposing First Division when he made landfall. Soon confronted by his brother, Hizashi apologised to Hiashi for standing before him as an enemy, despite the Branch House's duty to protect those of the main house.

Lamenting that this was penance for his defiance and that it even negated his desire to die for the sake of the clan and village, Hizashi remarked that this was simply the fate imposed upon him as a branch member. However, Hiashi refuted this and declared that Neji and Hinata were now fighting together on the battlefield, not to preserve the clan's bloodline, but rather as comrades defending one another. Concluding their dialogue, the two began to exchange blows.

Whilst they continued their fight, Hizashi was shocked to see Chōji's butterfly wings as it overshadowed the battlefield, before eventually being restrained by the latter's colossal fist. When Chōji departed to stop the Demonic Statue of the Outer Path's rampage, the other shinobi were left to deal with Hizashi.

Fourth Shinobi World War: Climax
With the cancelling of the Impure World Reincarnation, Hizashi's soul was released alongside the other reincarnated shinobi.

Legacy
Although Hizashi's death avoided a war between Konohagakure and Kumogakure, relations between the two villages ever-after remained tense. The circumstances surrounding Hizashi's death are well-known among the high-ranking ninja of Konoha, most of them taking it as a serious infraction on Kumo's part. Nevertheless, Konoha has tried to use the whole affair as a means of forcing cooperation from Kumo, citing the fact that Kumo still owed Konoha a great debt.

Hiashi chose not to tell Neji how his father died until he believed Neji was mentally ready. However, thinking they arranged his father's death, it only caused Neji to despise the Main House and believe that no one could escape from destiny. But when Naruto Uzumaki defeated him in the finals of the Chūnin Exams, Neji learned the truth from his uncle, who finally told Neji the truth. In the anime, Hiashi gives Neji a letter written by Hizashi before his death but in the manga, Hiashi shows his sincerity by bowing to Neji. Since then, like Hizashi before him, Neji decided to chart his own fate: dying a similar death during the Fourth Shinobi World War which his father was a reluctant participant via Kabuto's reincarnating him.

Quotes

 * (To Neji) "Neji… you must live. You are a man loved by the Hyūga talent more than anyone in the clan… I wish I could've born you into the Main Family."
 * (To Hiashi) "That is incorrect. I have hated the Main Family, honestly I still do… That is why, it's not for you as a member of the Main Family that I do this… I want to die and save you as my brother. Doing that is the first time I have the freedom to choose."
 * (To Hiashi) "I have only shown my ugly side to Neji… yet here, I finally understand my own will. So please tell Neji that I am not being killed to protect the Main Family, but to protect my brother, my family, and the entire village… I am choosing death with my own will."
 * (To Hiashi) "Brother… I wanted just once to disobey the Hyūga destiny. I wanted to choose my own destiny, that's all."
 * (To Hiashi after being reincarnated) "My brother… I'm so sorry… The Branch Family is supposed to protect the Main Family, yet here I stand as your enemy… I have no control over my body, perhaps this is my punishment for going against the Main House. The Branch House imposed itself on the Main House… this must be my fate."

Trivia

 * Hizashi's name means "sunlight", or "rays of the sun".
 * In the anime, during Tsunade's Infinite Tsukuyomi dream, Hizashi is the Masked Man, character of Jiraiya's novel.