The Blood Curse/the Blood Affliction.
To be a Kazima is to be cursed with an affliction requiring blood, a medium of iron. There have only been eight recorded beings of Kazima, of which only three were from birth. The three that were born into Kazima includes the first ever Kazima, Katsuhiro Kazima; one of the Seven Noble Warriors and his children, his son: Ichiro and his daughter: Akino. The other five were cursed by Ichiro and Akino.
Ichiro and Akino together perfected a jutsu which allowed them to transfer minute amounts of their energies to the receiver along with the curse which would then be assimilated into the host. Depending upon the amount of energy transferred when the jutsu & cursing was happening the host would assimilate the curse either slow or quickly and through excruciating pain of various degrees. The more energy given the more mind breaking the pain would be and would require recovery. Although the energy would be absorbed over time the curse would overtake the body quickly.
Ichiro performed the curse jutsu three times before his death, all three upon his students of the brightest and strongest. Their names have all but been obscured by the tides of history; however they fought with one another for heir apparent of the Kazima clan as small as it was. Lady Akino chose her first student and taught him the curse jutsu. Ichiro’s students having felt insulted left their village along with half of the Toshi Clan that resided in the Village alongside the small group of Kazima.
Two of the three students would return years later after the death of the first student alongside ninjas of the Toshi Clan not to make peace but war. Lady Akino, her first student (and heir apparent) died along with the two then remaining students of Ichiro. Before his dying last breathes it is said Lady Akino’s student cursed his own Daughter and showed her the cursing Jutsu. She quickly faded as she departed from the village and was never heard from again…
The Toshi would continue on after the war later through arranged marriages they would fuse with the Ichihiro Clan to become the powerful Toshihiro that still exists in the Taiyo Lands.