
Seishino Kanami is a member of the Nogakujin Clan, based out of Higuregakure. The Clan's origins lie not in nina warfare, but in theater. Noh plays was the specialty of the Nogakujin, ever since the concept of theatrical productions was formed in the minds of human beings, but the Nogakujin as a Clan did not come about until hundreds of years afterwards. Over time stage-craft became more refined, and select individuals became renowned for their skill and their ability to seamlessly merge into the roles of their characters (called "myoh"), while at the same time retaining the ability to synchronize with the performances of other the other actors — or characters, if the other actors likewise are capable of myoh. These individuals who displayed the ability to enter a state of "no-mind" (called "mushin") were recruited by an organization that sought to catalogue all the myriad Noh plays and cultivate a school for Noh actors, so that the beauty of the plays could be brought to the height of human capability, and thus enlighten and brighten the lives of the audience and actors both. This organization became known as the Nogakujin, or "People of Nogaku" (with Nogaku being another name for Noh).
However, the Nogakujin's purpose became clouded when the Clan Wars began, disrupting the period of enlightenment and forcing the Nogakujin to temporarily abandon their lives' goals. Many were forced to turn into beggars or street performers, trying to earn wages from the ailing economies of the villages they lived in, due to the war leaving countless people impoverished. But a core of Nogakujin retained their convictions, and determined that they must learn how to acclimate to new situations as well as retain the traditions of Noh. Thus, they began training in secret as ninja. Developing unique Hidenjutsu based off of their existing skills, as well as learning entirely new areas of skill, the Nogakujin began using their abilities to act as spies, saboteurs, and assassins. Few would suspect a performer of the vaunted Nogakujin to be a ninja. And with the newly developed tool of the Nogakujin, a Noh mask known as the "Mystic Noh-men", fewer still would be able to stop them.
Eventually the Clan Wars ended with the formation of the Hidden Leaf Village, and then the other Hidden Villages. The skill of the Nogakujin at conducting secret missions was no longer of practical use as an entity independent of the Villages. They had to join with these Villages, and serve under a Kage if they wished to continue their career as ninja — or so it would seem. But the Nogakujin had learned adaptability during the Clan Wars, and though their view of the world may have been forever changed by their experiences in war, the Clan was able to return to pursuing perfect beauty and enlightenment through the stage arts, while at the same time continuining to refine their ninja arts… Just incase.
Kanami was born during the Clan Wars, to a family of performers who were part of the "core" Nogakujin. Considering the fact it was war-time, she was raised under rather wholesome and loving conditions. When she lost friends and family members to the war, however, it became clear that she was a bit different from others. She didn't show any sign of sadness for the death of loved ones, or being disturbed when she was exposed to extreme violence for the first time. She took everything mildly. She was somehow "detached" emotionally from those around her and did not associate murder or violence with unpleasantness. This is not to say she was emotionless. She quite clearly possessed emotions. She just didn't value human life one iota. If someone died, the furthest she would think or feel on the matter was whether it inconvenienced her or not. She was more focused on the Noh plays that she studied, able to take on the role of any given character without difficulty, and then perform as that character to such an extent that she could fool even people who knew her well. When this was combined with her ninja skills, she became the ultimate stealth operative.
Kanami carried out many missions for the Nogakujin, but it was all for her amusement. When the Clan Wars ended, she had nothing to do other than resume "normal" performances. But Kanami did not distinguish between the two. To her, there was no difference between acting on stage and acting on a mission. A character was a character, regardless of the setting, or the purpose in performing as that character. She was the embodiment of the philosophies of Noh taken to an extreme. She could kill without any qualms and do whatever was necessary to fool her enemies. This was the sort of person desired by the man called "Amuro" for his own purposes. He needed secret agents who could remain hidden in plain sight. So, having heard of the exemplary skill of Kanami, and of her various exploits during the Clan Wars, he approached her in the Land of Rivers prior to the Takokujin's arrival there. He recruited Kanami from Higuregakure and explained to her his needs and some of his plans. Intrigued by the idea of returning to the exciting world of ninja missions, Kanami accepted the offer. She has been with Amuro ever since.