Kazuto is a mysterious man with short wavy raven black hair, grey eyes and stubble. He always seen wearing a black cloak, but underneath he wears a skin tight sleeveless top, black leather gloves, black trench trousers, and brown leather boots. Several scars decorate his arms.
Gruff, stubborn, and hardheaded – words that could easily describe Kazuto’s usual demeanor. He treats the majority of the main cast as children, issuing them warnings about how they are not strong enough to deal with the tasks at hand, while also calling them “brats” at the same time. He has a certain amount of respect for his own opponents, honestly listening to Drei’s story of his own life without interrupting.
Despite his gruff exterior, Kazuto has a soft side, going out of his way to save Hinata Himezuru from a life made to control humanity. Although it’s unknown what he did, Kazuto has a close relationship with Yuki Himezuru, and would do anything to protect her and her family.
Nearly always wearing a black cloak, Kazuto’s true face is rarely ever seen. He is well aware of the serial killer: Ripper, and is hunting him down. He has some sort of connection with the Mitsurugi Agency and is a bounty hunter whom specializes in tracking down Unions. Avenge is associated with the Magick Association, despite this, he is unable to use sorcery. In exchange for this handicap, his knives are enchanted with a spell that allows the wounds dealt by them to be impossible to heal via sorcery. He has been hired by the Magick Association to assassinate the renegade Ten Sages - Drei, Acht, and Sechs.
Three years before the events of Code: Embryo, it’s hinted that Kazuto was in a relationship with Ryōko Kagari.
XBlaze – Code: Embryo
Having tracked down Ripper, Kazuto cornered him when he was in the middle of fighting Es. The two battled as Kazuto told the young girl to stay out of his way. Despite having put up a tremendous amount of effort in battling the Union, Tōya Kagari and Mei Amanohokosaka arrived, leading Ripper to run away out of 'boredom'. He turned his attention to the new arrivals, immediately butting heads with Mei due to an obvious personality clash; he ended up knocking out Tōya when he rudely tried to defend the young girl. He told them to stay away from Ripper and quickly disappeared.
He suddenly appeared behind Yuki Himezuru, telling her to not turn around. Kazuto told her that dangerous things were happening in the city, and that she should take her family and leave. Hearing her rejection to the warning, he left, albeit confident in everyone’s abilities to protect themselves.
After Tōya had unleashed his Original Grymoire, Kazuto found Ripper down in the sewers, severely weak from having all his magic element drained. The two fought, but Kazuto easily had the upper hand and ruthlessly murdered the serial killer with the precision of a true assassin. He left the sewers, and made a prayer for Yuki, to let her know that he had avenged her.Kazuto found Es and Tōya down in the sewers of the city, and guided them through it, taking them to a relatively safe location. Here, Es filled him in on the Embryo and it’s true powers. Their time was cut short as several of the Agency’s soldiers came their way. He told the teenagers to go on without him, and that he would handle them himself. He later came to their rescue once more, taking on Drei one-on-one. He respectfully listened to the Sage’s story about his life before they had their mortal duel.
Having killed Drei, Kazuto thought he would soon die from his wounds too, fortunately, Marceline F. Mercury jumped down the sewers to his aide, giving him a brief patch up with her healing sorcery. She requested that he go and prevent any Agency soldiers from getting in the way of Tōya and his friends while they infiltrated the restricted ward – he gladly agreed.
XBlaze – Lost: Memories
Two months after the Embryo Incident, Kazuto was apparently not around during the Vampire Incident, unaware that his mortal enemy, Ripper has revived himself as Freaks through the young man Kiri. However, he never found out as Tōya and the recently revived Es has finally slayed his eternal enemy once and for all. Some time after Freaks’ death, Yuki would invite him to introduce him properly to everyone she knows, including Es and a surprised Tōya and Mei.
Powers and abilitiesAn extraordinary human, Kazuto’s martial skills are nothing too scoff at. His skills with knives are beyond that of the average human, being able to take on Ripper in combat with nothing more than his own power. To help put him in an advantage, Kazuto has knives that are enhanced via sorcery to prevent wounds from healing, giving him an edge in combat against those who can apply healing sorcery. A testament to Kazuto’s power is that he was able to not only fight, but actually kill Drei of the Ten Sages by himself.
Having observed Ripper’s fighting style from their many encounters, Kazuto developed his own smoke bombs to help him in combat, although they are rarely seen.