AppearanceIn order to extend his life after contracting the Death disease, he implanted many Medusa Eyes in the left side of his body.
Hishigi wears a mask covering the left side of his face to hide the Medusa Eyes and conserve their power that keeps him alive.
He has black hair (though it sometimes appears dark blue) with a white streak on the left side. He wears a black leather longcoat with no sleeves, a black shirt, and black pants that cut off just below the knee. His left arm and leg are entirely bandaged to cover the Medusa Eyes. His weapons are a massive sword, Hakuya, and an unnamed dagger.
PersonalityHishigi is stoic and rarely shows emotion during his appearances in the story. He demonstrates unfaltering loyalty to his friend Fubuki, but expresses that he has grown tired of fighting for the flawed and arrogant Mibu Clan as a whole. He is intensely bitter and resentful toward the True Mibu for creating flawed Battle Dolls such as himself, and hates them for leaving the genetic flaw that resulted in the Death Disease. His primary motivation is protecting Fubuki.
Muramasa, Fubuki, and Hishigi were once best friends. A flashback shows that when Muramasa left the Mibu Clan, he asked Hishigi to come with him. Hishigi chose to stay and spend his remaining years protecting Fubuki.
StoryHishigi is first seen talking to Fubuki after Fubuki tells Shinrei that Taihaku is dead. Hishigi appears after Shinrei has walked away and comments on the fact that Fubuki forgot to tell Shinrei that it was he who had killed Taihaku and not Kyo. Fubuki tells Hishigi that if he does not like his methods, he could leave the Mibu Clan like Muramasa. In response, Hishigi tells Fubuki that he made his choice to stay with the clan even if it meant walking down the path to Hell. Hishigi next appears with the assembled Taishirou to welcome Kyo and his group to Onmyoden.
After Kyo's group falls to the underground layer of the Red Tower, Yuya sees Hishigi talking to Akari. Much to her surprise, it is revealed that Akari was originally a spy sent by Hishigi to gather information on Demon Eyes Kyo. Hishigi refers to Akari his best soldier and trusted friend. The fact that Hishigi has resurrected Shatora, also known as Yuya's brother Nozomu, also comes to light in this scene.
During his battle against Kyo, he throws himself in front of Fubuki to protect him from Kyo's Suzaku. The damage from this attack destroys Hishigi's Medusa Eyes, and he collapses as the Death disease (which he contracted due to the inherent genetic flaw present in all Battle Dolls while researching it) continues to destroy his body.
As Hishigi loses consciousness, he dreams about the day he implanted the Medusa Eyes in his body and his conversation with Fubuki afterward. The flashback reveals that Hishigi has an exceptionally aggressive case of the disease. After Fubuki says that he wants his friends to survive "no matter the state", Hishigi calls him selfish and tells Fubuki that he cannot imagine the peace he would feel if someone would simply kill him. Fubuki refuses and drags Hishigi to his feet, saying that Hishigi is required to live until Fubuki does not need him by his side anymore. Hishigi agrees and says he will be Fubuki's sword and shield until the day he dies.
Hishigi wakes up to find Akari attempting to heal him, and he tries to convince her to let him die because he is a monster not worth saving. Akari claims that she isn't saving him just for his sake, and that if he dies, she will lose another person who is important to her. In the official English translation of this chapter, she tells Hishigi that he is not allowed to choose death for himself as long as someone will mourn his passing. Yuan is moved by Akari's desperate pleas, and he pulls Hishigi to his feet, saying that his mother Ian taught him to help anyone he was able to. Hishigi appears startled by the protagonists attempting to help him, and looks at Fubuki who is currently fighting Kyo. Hishigi then abruptly pushes Yuan away and transfers his memories to Akari (so that she might continue researching the Death Disease), and she collapses on the ground. As Akari lives his memories, she discovers that Hishigi loved children and he felt useless when he couldn't find a cure. Hishigi places a force field around Yuan, Akari, Julian, Shinrei and Hotaru to protect them from his last ditch attempt to kill Kyo.
Hishigi dies after giving his heart to Fubuki so that he would survive after destroying his own heart during his battle against Kyo. Fubuki screams at him to stay away, not wanting Hishigi to sacrifice himself, but Hishigi refuses to back down. Hishigi dies telling Fubuki not to remember their time together, as it would bring him pain, as well as regrets to Muramasa that he couldn't uphold their promise. In the English translation released by DelRey Manga, Hishigi tells Fubuki that he is not allowed to blame himself for Hishigi's death and that Hishigi chose his own path. As he dies in Fubuki's arms, he hopes that Fubuki can find the heart to forgive him. Just after his death, Akari sees the last memory he left for her: the day he told Fubuki that he would be appointing a shaman as his imperial guard. The memory reveals that he called her Number 13 because he would feel too much emotion for her if he called her by her name, and that he believes they would have been close friends if they had met under different circumstances. Upon his death, both Akari and Fubuki react with sadness and anger, as Hishigi was Akari's mentor and was Fubuki's best friend. Tokito later notes his death with surprise, wondering how Hishigi could have lost and died. Later, the spirits of Muramasa, Fubuki, Hishigi appeared and revived Julian, Shinrei, Tokito, Hotaru and Yuan, who had been "turned off" by the Former Crimson King (Sendai Aka no Ou).
Abilities / Notable AttacksHe wields a huge sword named Hakuya (translation: “White Night”). Julian designed and forged Hakuya for Hishigi, because Hishigi was so strong that he shattered lesser blades. With this sword, Hishigi can perform a slash at the speed of light, which he uses against Yuan (another one of the Taishirou) and Kyo.
Hishigi also wields a dagger , but he rarely uses it
It is rumored that Hishigi is the strongest Taishirou in history, and for this reason he is called "the Executioner". He is on par with Yuan even before activating his Red Eyes, and clearly Yuan's superior afterward. Fubuki also says that Hishigi is the "most powerful" of the Tashirou since Muramasa left. Despite being on the brink of death at the end of his final battle against Kyo, he is able to create barriers so strong that neither Fubuki nor anyone in the protagonists' group can break free of them.
- Fog (or Mist)This is a ninja technique: Hishigi utilize a sort of "fog" to leave battlefield (similar to Saizo and Tokito )
- Memory Transfer
He can transfer his memories to others
- Lightspeed Slash (Energy Blades)Hishigi fires a large, arch shaped energy projectile from his sword to strike a distant target. He is shown to be capable of creating seven of these blades at once. Despite this attack's name, the general consensus is that it does not move at the speed of light.
- Red EyesHishigi can call out to the Mibu blood within him for significant boost in power, which changes his eyes to crimson red.
- Forcefield (or Hishigi Barrier)
Can create a forcefield to trap his opponents in. The barrier can be protective of outside threats as well as imprisoning those inside.
- Pseudo self-destruction (or detonation)Hishigi uses his last spiritual energies to create a violent explosion and take his opponent down with him.
- Soul "Awakening" (after death)The spirits of Fubuki, Hishigi and Muramasa gather to wake up Julian, Shinrei, Tokito, Hotaru and Yuan (who were "turned off" by the Sendai Aka no Ou).
- It is implied that Hishigi is the one who attacked Shihoudou on the Former Crimson King's orders after she allowed Kyo and Muramasa to leave Mibu territory.
- Fubuki and Hishigi carry swords made by Julian (not surprisingly, considering that Julian was Muramasa's master and the Mibu Clan's greatest blacksmith), because a master swordsman has so much power that a lesser sword will break under the stress.
- The cat that Fubuki resurrects and carries around on his shoulder is black with a white left ear, and fans have noticed its resemblance to Hishigi.
- Hakuya bears some resemblance to Mihawk's Yoru in One Piece
- His Medusa Eyes have some similar qualities to Danzō's Sharingan from Naruto.