Ōko Yushima

is a Shinigami of the 12th Division and worked in the Shinigami Research and Development Institute. He was the developer of Mod Souls.

Appearance
Yushima bears a great resemblance to Kageroza Inaba, having long green hair and brown eyes but a more narrow jawline and less-define cheekbones. During his time with the Tenth Division, he wore the standard Shinigami shihakushō. After he was transferred to the Twelfth Division, however, he donned a long yellow robe that buttoned up in the front and protruded upwards from his neck, covering the entirety of the back of his head, in the same fashion as Kageroza Inaba's attire.

After being resurrected by the fusion of Inaba and Nozomi, he wears a standard Shinigami attire with a yellow under shirt, light blue gloves, and a light purple belt loosely around his waist to hold his Zanpakutō.

Personality
Yushima comes across as shy around others. Despite this shyness, Yushima cared little about being with others, believing that relying on others will only have them get in the way. He wanted greatly to prove himself to others. When he became a researcher, he took great pride in his work, becoming deeply enraged when the Central 46 canceled Project Spearhead, screaming at them while demanding a reason for why they shut down the project and doing everything he could to preserve that research.

History
Yushima had a difficult time graduating the Shinō Academy. During which, his combat skills were poor, causing him to feel others looked down on him. When he eventually graduated, he was placed in the 10th Division. However, ninety-six years before Inaba's uprising, he was transferred to the Twelfth Division and the Shinigami Research and Development Institute, because his superiors thought that he was not cut out to fight, but as he was smart and a hard worker, he was a better fit with the S.R.D.I.

He was the leader of Project Spearhead, but the Central 46 discontinued the project, leaving Yushima enraged, demanding an explanation. In an attempt to preserve his research, Yushima tossed the data on Mod Souls into the Dangai, and transferred some of his memories to Kageroza Inaba, a mod-soul he had created, just as the Shinigami came to arrest him. This left him in a seemingly catatonic state. He was subsequently placed in the Nest of Maggots.

Gotei 13 Invading Army arc (anime only)
Note: Events occurring in this arc are only in the anime and do not constitute canon material.

Yushima is confined to a cell in the Nest of Maggots where he sits in a chair, un-moving. When Kageroza returns to Soul Society from Karakura Town. Kageroza visits his cell, commenting that it is useless to run from him. Kageroza then laughs wildly.

Later, after his confrontation with Retsu Unohana in the Institute, Kageroza returns to the cell. He reassures Yushima, stating that Nozomi will return to Soul Society without fail.

Once the Reigai defeat the captains, Inaba returns yet again, after having a disturbing dream. He goes to Yushima and asks him why he is worried. He tells him that everything is going to plan. Inaba asks if he is worried about Nozomi, saying that it is only a matter of time. Coughing up blood, he explains that he expected to be injured by the originals as they are not fools. He tells Yushima that he will see to it that the world will learn of his wish.

Later, Kisuke Urahara and Kon find him in the Nest of Maggots. Kon attempts to make him speak, but Urahara states that he may never regain consciousness. Later, after Inaba succeeded in fusing with Nozomi, it resurrected Yushima as a Mod Soul. He then appeared before a Hollowfied Ichigo Kurosaki, looking down on him in pity. As he calmly walks pass Ichigo, the now mindless Hollow attacks with a Cero, only for Yushima to effortlessly dodge. He goes off to watch his Reigai battle with delight. His enjoyment is cut short as Hollow Ichigo finds and attacks him again. Yushima again takes little interest and subdues him with a "Kin" spell. He releases his Zanpakutō and strikes to slay Ichigo, only for his attack to be stopped by Rukia Kuchiki. After a simple display of his new abilities, he is impressed by Uryū Ishida deducing the true workings of his blade, prompting Yushima to fight seriously. As the group launch collaborated attacks, Yushima easily dodges or records their attacks. Still feeling unthreatened, Yushima calmly explains that the reason he wanted Nozomi was to obtain her Zanpakutō's reishi absorbing power so he could make full use of his own Zanpakutō's abilities. After soundly defeating his enemies, he with a deranged expression declares that he will destroy Soul Society. Before can strike down Rukia, his attack is intercepted by Hollow Ichigo, he uses his own body to take the blow.

Inventions
Kaizō Konpaku: Yushima created the mod souls that were manufactured under Project Spearhead, including Kageroza Inaba and Nozomi Kujō.

Powers & Abilities
Master Scientist and Inventor: While as a Shinigami he was inept in combat, he was noted for being very intelligent, ultimately getting him transferred to the 12th Division's Research and Development Institute. There he was responsible for creating the Mod Souls.

Expert Swordsmanship Specialist: After becoming a Mod Soul, Yushima displayed considerable sword skill, able to quickly overwhelm his opponents even when outnumbered.

Immense Spiritual Power: After becoming a Mod Soul, as a combination of Nozomi and Inaba, Yushima displays considerable reiatsu, able to be felt from various Shinigami from a large distance.

Kidō Master: After becoming a Mod Soul, Yushima showed skill in Kidō, able to perform high-level spells quickly and effortlessly, even up to level 99.

Shunpo Expert: After becoming a Mod Soul, Yushima obtains considerable speed in battle, able to dodge several attacks from multiple opponents unscathed.

Enhanced Strength: As a Shinigami, he was physically weak. After becoming a Mod Soul, his physical strength was dramatically increase, able to repel a Shikai blast with a single bare-hand.

Zanpakutō
takes the form of an ordinary katana with a golden hilt with a red cloth-wrapping and maroon sheath. It has a rectangular tsuba with a cross shape embossed on it. As a Shinigami, Yushima wore it on his sash. As Mod Soul, it is attached to a loose belt.


 * Shikai: When released, the katana turns into a double-headed voulge with red markings on it. With the combined powers of Kageroza and Nozomi fused, Yushima's Zanpakutō becomes an amalgamation of both their swords, having Raiku's form but with more blade protrusions on the back end of both blade tips similar to Arazomeshigure.


 * Shikai Special Ability: Duplicating an adversary's attack and reproducing it is the power of "Raiku", absorbing an adversary's spiritual pressure and turning it into one's own is Nozomi's "Arazomeshigure". Sumitsukigasa possesses the power of both. "Raiku" consumes a great deal of Yushima's spiritual pressure and entails a risk when reproducing an adversary's attack, but with the power of "Arazomeshigure", He is now able to absorb the attack and continue to counterattack indefinitely.


 * Spatial Displacement: his Zanpakutō takes slices of space and recreates them. While it appears that he is manipulating time that is not what he does at all. He uses his Zanpakutō to recreate a space that didn't exist before and shifts his location in space in that instance.


 * By using the release command . Sumitsukigasa glows yellow and transforms further gaining a large hoop with multiple bladed protrusions along the outside of it. The hoop is set into the middle of the of the voulge bar where the weapon is commonly held and twirled.


 * Attack Duplication/Reiatsu Absorption: By spinning Sumitsukigasa right the central hoop glows pink allowing Yushima to absorb any attack that his Zanpakutō comes into contact with. When he spins Sumitsukigasa left the central hoop glows pink and fires the absorbed attack back. This is the true power of his Zanpakutō.


 * Bankai: Not Yet Achieved