Mitsuyoshi

Jubei is one of the Six Heroes. He is Konoe's husband and Kokonoe's father. He is also the progenitor of the Kaka race.

History
Jubei is one of the Six Heroes, Ragna the Bloodedge's master, and Kokonoe's father. He battled the Black Beast alongside Hakumen, and played a part in the Ikaruga Civil War. The Kaka Clan were genetically engineered from his DNA. Despite his physical appearance, he is a powerful warrior. He works to safeguard his friends in their times of need. Before the start of the series, his partner Konoe was murdered by Yūki Terumi. Jubei has a relatively awkward relationship with his daughter, the reason being that he left her in the care of the Novus Orbis Librarium for a large portion of her childhood, while never visiting. After the emergence of the Black Beast in Japan, Jubei was left as the sole survivor of his clan, with his brother, Tomonori, having been killed by Terumi.

For an unspecified amount of time, Jubei worked for Clavis Alucard, and in BlazBlue: Phase 0, went on to be sent to confirm the death of Shūichirō Ayatsuki; should he have found the man alive, Jubei was to assassinate him. Jubei's workings with Clavis were known among the Ten Sages, Nine going on to call him "Clavis' pet cat" when they first met.

Alongside his moniker as the strongest being on the planet, Jubei is sometimes referred to as the Mitsuyoshi. Before Jubei met Bloodedge, he went by the name of Mitsuyoshi; after the death of Bloodedge, who frequently called Mitsuyoshi as Jubei, the Beastkin went on to adopt the name Jubei in memory of Bloodedge's sacrifice.

In BlazBlue: Phase 0, the reason why he wears an eyepatch is explained. He sustained severe injuries around his body including his right eye while trying to protect Bloodedge and Celica from a small remnant of the Black Beast. He replaced his eye with his brother's eye: the Sekigan (隻眼), and wore an eye-patch over the replacement eye itself.

After the War, Jubei was unfortunately left as one of the few survivors of the Six Heroes, Terumi having killed Nine and Trinity Glassfille and forcing Hakumen to sacrifice himself. He was on the run from the organization for many years afterward, being forced to abandon his daughter Kokonoe.

After the fight with Terumi, Jubei visits Celica and tells her about of what has transpired. Before leaving, he asks Celica to protect the Church and the Black Beast's remains, as he is sure that Terumi will return. He also promises her that he will return. Shortly after that, he starts out with investigating the death of Nine and Trinity, as according to him, there were a lot of pieces that didn't add up. His next step in mind was completing Nine's work of retrieving all of the phenomena weapons, releasing their cores and sealing the artifacts. In the span of the next decades, Jubei was able to retrieve only one Nox Nyctores, Arma Reboare: Muchōrin, which he had left in Rachel's care after she had woken up from her slumber. A few years later, while traveling the world, in a lab knew to few, he meets a boy with golden hair and a single jade-green eye. A few days after that, together with the boy, his brother and sister, Jubei, while being covered in wounds, returns to the church. He leaves the children in Celica's custody.

He would again return to the church years later and train Ragna.

During BlazBlue: Calamity Trigger, he is shown to be wandering around Kagutsuchi, appearing in the story modes of Ragna, Hakumen, Tager, Litchi, and Taokaka, as well as briefly during the true ending.

Shortly before the events of BlazBlue: Chronophantasma, Jubei trains Jin to use the Power of Order properly, as well as inform him of many topics regarding Ikaruga and the NOL such as the Izayoi. He arrives in Ikaruga after his pupils and reunites with Rachel Alucard, Celica, and the remaining Six Heroes. In order to materialize Terumi's true form, Rachel uses the memories embedded in Jubei's right eye, the eye of his brother Tomonori who managed to wound Terumi's truest form. Near the end of BlazBlue: Chronophantasma, Jubei fights off-screen with Phantom, who is revealed to be his thought deceased lover, Nine. As Phantom returned to Hades Izanami afterwards, Jubei's fate was currently unknown. It is in BlazBlue: Centralfiction that he appeared again saving Rachel from Terumi, and saying to her that she was exceeding herself.

Appearance
Jubei is a two tailed, black and white cat, who stands upright like a human being. He wears a jacket similar to the Kaka clan's jacket, but with an Eastern motif and a cut in the back where his two tails poke out. He also wears an eyepatch on his right eye, although it is hardly seen due to the game's affinity to flip and reuse the same sprite. His weapon, the Musashi, is carried on his back via a belt strap.

When he was young, he wore a Kaka ninja-like orange-yellow garment.

During the Dark War, he wore samurai-like armor.

Powers and abilities
Jubei's powers, or at least the extent of them, have never been shown within the series thus far. However, being one of the Six Heroes, he is likely exceptionally powerful. Claimed by several, amongst them Hakumen and Terumi, to be the strongest creature alive, it is implied that Jubei is nigh-undefeatable in combat as none have dared to engage in battle against him. This is furthered by the fact that when he catches Hazama off guard in Hazama's gag reel Hazama seems to just accept the fact that Jubei will kill him and doesn't even try to put up a fight. His training of Ragna seems to attest to a great power. He wields the Nox Nyctores, the Mucro Somnio: Musashi. With it, he seemed to be able to cleave the shell of darkness that Phantom had surrounded Lambda with during her fight with Nu, but nothing more is known about it. As Jubei's mental faculties do not appear at all to be affected by the weapon in any way, it can be assumed that his mind is very resilient.

Underneath his eyepatch is the eye of his deceased brother, which contains an ability called Sekigan (隻眼). As Tomonori has seen Terumi's true form, this eye can force his true form to materialize. Jubei has used this ability on two occasions: once in the past to help Hakumen seal Terumi away, and again during BlazBlue: Chronophantasma as part of a plan to destroy Terumi once and for all.

Personality
Jubei is generally agreeable, sociable and optimistic. Whenever there is a great threat, such as Ragna or the NOL around, he always keeps his laid-back attitude and stays relaxed. He makes the best of every situation, and is always trying to see the good in everything.

At times, though, Jubei shows a far more jaded and bitter side. Due to many of his friends having died, Jubei shows deep-seated guilt over his inability to do anything. As such, he has felt that he is nothing more than a weak coward who runs home with his tail between his legs while leaving good people such as Hakumen and Bloodedge to their fate. The supposed death of his lover, Nine, and having to leave their daughter Kokonoe without a family, only wound him further. Because of those losses, however, Jubei is even more driven to do what's right, and will use the power he has to do so.

Trivia

 * Jubei appears to be a bakeneko (specifically a nekomata), a mythical two-tailed cat said to be created when a normal cat grows to a certain age or size. In traditional myths, bakenekos would eat snakes, perhaps a reference to Hazama's hatred of cats (aside from his allergies).
 * Due the fact that he is wearing a tsuba for an eye-patch and wielding two kodachi, he appears to be named after Yagyū Jūbei Mitsuyoshi, a historical Samurai known for having founded the highly aggressive "Yagyū Shinkage Ryū" school of swordsmanship, and for wearing a tsuba for an eye-patch.
 * Jubei is actually the one to finish the enemy (or perhaps rescue the enemy from Taokaka's fatal blow) in Taokaka's Astral Heat.
 * As it is hinted in Noel's story in BlazBlue: Continuum Shift, Jubei cooks food that comes from a five-star restaurant, hinting that Ragna picked up cooking skills from Jubei during his training, as stated in the Material Collection.
 * While Jubei is able to resist any mental affects from his Nox Nyctores, Musashi, it is shown in Hazama's gag reel that he cannot resist any of his cat-like urges when it comes to catnip.
 * In Hakumen's history, it is revealed that the person who Bloodedge gave his life to protect is actually Jubei.
 * In Chronophantasma's Tutorial Mode, Jubei will guide the player through the section Stylish Lesson - Application.
 * In Chronophantasma's Story Mode credits, Jubei's name is spelled as Juubei.