The Story of a Boy

Hizumi is first introduced to the reader during the 10th volume of Spiral: Suiri no Kizuna as the younger brother of the father and creator of The Blade Children, Mizushiro Yaiba. Hizumi, like the series protagonist is sixteen years of age. This puts him at an age where he died after Mizushiro Yaiba's plan had begun and before his death. Despite being "brothers" the two never met in person and Hizumi grew up without knowledge of his "brother", instead being raised by a family with no children of their own.

At the age of ten his adoptive parents revealed to him the truth of his birth. They were fringe members of Yaiba's organization who were asked to raise Hizumi as their own. Hizumi was not Mizushiro Yaiba's brother but rather his clone.

Soon after being told of his original's existence as the 'devil' and his fight with the 'god' Kiyotaka Narumi he was faced with the knowledge that he was destined to descend into madness like Yaiba before him. This causes his parents to distance themselves from the child they raised as they are forced to acknowledge the possibility that he could become a monster. Rather than being disheartened by his fate it only spurred Hizumi on. He sped through his remaining years of school until he was able to enter college in America at the age of thirteen.

While in college he studied genetics in an attempt to defy fate and save The Blade Children from their curse. It was there that he discovered just how unsafe and unproven the idea of mammalian cloning, let alone human cloning was. He discovered that he had a minuscule chance of living long enough to go mad. The knowledge of his own humanity and the constant interference from Kiyotaka Narumi made Hizumi lose hope. He tried to kill himself several times only to find that he would be unable to die by his own hands, per the devil's plan.

At the age of sixteen Hizumi returns to Japan to meet a god of his own, our protagonist Ayumu Narumi. Ayumu is supposed to be the ‘savior' of the blade children and has been fighting them repeatedly in order to prove himself. Little does he know that his older brother Kiyotaka has been controlling things behind the scenes and that included the appearance of Hizumi. Hizumi was sent by Kiyotaka to force Ayumu into a corner and while Hizumi attempts to complete his mission he find himself drawn to Ayumu and his insistence that he can fight fate once more.