|Previous Affiliation||Soul Society|
|Previous Occupation||3rd Seated Officer of the 6th Division|
|Previous Team||6th Division|
|Partner||Kirei Satoshi, Alexander Saito|
|Previous Partner||Muramasa, Ginrei Kuchiki|
|Base of Operations||The Valley of Screams|
|Relatives||Unnamed Wife, Ginrei Kuchiki (Father-in-law), Byakuya Kuchiki (?), Rukia Kuchiki (?), Hisana Kuchiki (?, Deceased)|
Kōga Kuchiki (朽木 響河, Kuchiki Koga) is a Shinigami introduced in the anime-exclusive Zanpakutō Unknown Tales arc as an antagonist. He is a former 3rd Seat officer Shinigami of the 6th Division who once revolted against the Seireitei. He was also a member of the Kuchiki noble family, having married into it. He currently goes by the name of Koga Senryu(古賀川柳, Senryū Koga, "old river willow" ) and is now allied with Kirei Satoshi and his Liberation Army.
Kōga is a tall and well-built Shinigami with very strong green colored eyes, dark purple hair with a long braided pony-tail of rich pink hair, and bangs that hung on the right side of his face to frame it. Back during his days as a Shinigami of the 6th Division, in addition to a standard Shinigami attire, Kōga also wears a long red scarf, light purple obi sash, and a beaded-necklace with a pendant. He also wore an intricate white headpiece called kenseikan on the left side of his head to symbolize his nobility that held his ponytail in place with red tufts of hair sticking out (which he later cut off to relinquish his status as a Kuchiki). While originally his appearance was youthful and fit, after several hundred years sealed away, his physical form has been reduced to a withered-old version of his former self.
In the past, Kōga was a man with a true sense of duty and a commitment to making his family proud. He always tried to remain humble and serious to situations at hand. On the inside however, Kōga was a man who deeply desired to be acknowledged for his abilities and hard work. After realizing that his life as he knew it was gone forever, he had a mental-breakdown, causing him to become consumed by his anger and desire to stand in greatness, leading him to become immensely arrogant in his power to the point of viewing all others as worthless, even his own Zanpakutō, Muramasa.
After his defeat at the hands of Byakuya Kuchiki, and his subsequent death, Koga after being saved by Kirei has once again returned to his nobler personality, he is now much calmer than he was before, and does not desire power or any recognition as he now knowns for himself that he is a superior warrior. Though he still bears a great grudge against the Kuchiki family especially Ginrei and Byakuya, this is also the reason why he changed his name and cast aside his Kuchiki title. He is now a man of great honor, as he is willing to fight against his enemies fairly, he has also shown signs of compassion to others. The relationship with his new zanpakuto Ginkiri is different than the one he had with his previous one, as he now genuinely cares for her, and wishes to know more about her so that they may grow together in power and strength. This change of personality stems from the fact that he almost died once due to his own arrogance and the many terrible decisions he made. Koga regrets what he did to his previous zanpakuto and partner Muramasa.
Several hundred years before the main storyline, Kōga was welcomed into the Kuchiki family as the son-in-law of the Ginrei Kuchiki. He soon gained much respect throughout Soul Society. Unfortunately, the one person Kōga wanted to be acknowledged by, his father-in-law Ginrei, always looked at him with indifference and put him through tests. The only person to ever comfort Kōga at all was his Zanpakutō Muramasa. Kōga later became a powerful ally in a civil war. When it became clear that he may very well be the key to winning the war, the enemies, which included three elites, came up with a plan to frame him as a traitor. He was later freed by Muramasa who inspired him to take control of his life again. Kōga then did so by killing the elites who framed him. But it was only after he did so that he realized he made a mistake. Realizing his life was forever ruined, he went insane and decided that everyone was jealous of his powers, thereby meaning he had to crush all others to stand tall in the world again and soon revolted against the Seireitei. As he killed more people, his instability grew, soon even abusing Muramasa when he was anything less than absolutely obedient. This disharmony between them gradually caused Kōga to lose his ability to communicate with and even access Muramasa's power. Genryūsai Shigekuni Yamamoto and Ginrei Kuchiki were eventually able to seal Kōga away when he lost total access to Muramasa's power. Kōga's revolt was never recorded in the Soul Society's history.
Muramasa is once again seen in Bleach - Generation III along side his previous master Koga Kuchiki, it seems they have once again joined forces, and Muramasa has forgiven Koga for his previous betrayal and is glad to be reuinted with his old master. It is currently unknown how they were able to meet with each other but it is assumed that after it was revealed that Ryan was a zanpakuto and reuinted with his own master, he left Muramasa behind. Muramasa once again without a master wandered the human world untill he met with Koga.
Muramasa (村正): Kōga's Zanpakutō, now Ryan's former partner, takes the form of a katana with a dull red sheath, purple hilt-wrapping and a guard in a shape similar to the Kidō Corps' emblem, consisting of a circle with a pentagon-like shape in the center and three points protruding from the edges evenly spaced apart. Muramasa is an illusion-type Zanpakutō.
- Shikai: The release command is "Whisper" (囁け, sasayake). Muramasa shines with bright purple light to engulf a considerable radius, affecting any and all targets within it.
- Shikai Special Ability: Muramasa can break into the inner world of targets, similar to how a tape-worm leeches off its target, and forces them to bend to the user's will. It can cause a Zanpakutō's spirit to abandon its master and attack them. The ability causes the Zanpakutō's of the wielders in the general vicinity to seemingly take control of the wielders sword arm causing him/her to unwillingly attack their comrades or turn the blade on themselves. The only way to combat against Muramasa's power is by understanding how the Zanpakutō works and sealing ones "heart" against it. Though in order to block the attack in that state one must have incredible reiatsu and concentration. In addition, one must be able to still fight in that state.
- Yūkōjōchū Muramasa (有鉤条虫村正, Hooked Tapeworm Muramasa): Muramasa himself has the ability to manifest in his true form and even can manifest himself at a distance from Ryan, able to hear his call from wherever he is. Upon doing so, Muramasa has the ability to cause other Zanpakutō to manifest by controlling and warping their true instincts to the point of removing their ties with their Shinigami. When this takes place, the Zanpakutō of other wielders glow with a purple light. Their Zanpakutō spirits then manifest, typically as tangible shadowy figures from weaker Shinigami and with greater individuality and power from stronger Shinigami.
Equipment Powers & Abilities
When using Muramasa, he gains a few abilities that aren't attributed to the zanpakuto, but rather Muramasa gives his reiatsu the uniqueness to preform these techniques.
Illusions: By channeling his spiritual energy into his opponent, Koga is able to distort the target's perception, effectively making a person's five senses unable to properly register what is happening. This power can be negated by one using their spiritual energy to close off their emotions before the hypnosis takes place.
Spiritual Threads: Koga is able to form invisible spiritual threads like Muramasa to bind his opponent in place. These threads are visible on reflective surfaces such as ice.
Garganta: He was seen using a variation of this technique to travel to and from the Soul Society. Although the way he uses it is slightly different from how the Arrancar use it. Instead of causing the portal to open by "splitting" the air apart in a segmented pattern, he seemingly tears it open, similar to how the Menos Grande use it. Muramasa lends him this power whenever he needs it due to Muramasa having absorbed many Hollows.
Powers & Abilities
Master Swordsmanship Specialist: Kōga was an immensely powerful combatant, even with only his sealed Zanpakutō. Back when he was only a 3rd seat officer, he was able to easily fight at captain-level and take down a large group of enemies attacking him at once. His skills are very versatile, able to use various bladed weapons with high proficiency. After his battle with Byakuya, he trained for several years honing his skills and greatly improving them.
Flash Step Master: Kōga has demonstrated highly proficient skill in Flash Step, able to keep on equal footing with Byakuya Kuchiki, one of the most skilled masters. In battle, Kōga has shown great enough reflexes to dodge point-blank sword attacks unscathed. He skills in flash step have further improved, being able to keep up with the likes of Aoko Sonozaki and Kagami Kyosuke, both of whom are well known for their mastery over flash step.
Kidō Master: Kōga's skill in Kidō is immense, able to use various forms of spells with great power and skill; all at the same time without incantation. He is also able to produce powerful barriers to protect himself from all but the strongest of dangers
Enhanced Strength: Even in his physically withered state, Kōga is deceptively strong. With a single downward chop, he was able to snap his sword's blade in two. After several years of training and honing his skills his strength has also greatly increased, he was able to beat an adjuhas class menos with his bare hands.
Expert Hand-to-Hand Combatant: Koga has also shown himself to be a highly proficient fighter even when unarmed. During one of his training session's, Koga demonstrated great skill by incapacitating several possessed Shinigami. In battle, he has shown himself to be tremendously agile and is able to attack from various angles with great dexterity.
Immense Spiritual Power: While not a noble by blood nor of considerable age, Kōga possessed great spiritual power even when only a 3rd seat officer. Ginrei, the 6th Division captain at the time, states Kōga's power vastly surpasses his own. He displays a massive reiatsu, even after being sealed away for several centuries. His spiritual powers have further increased since his battle with Byakuya, as he was able to refore himself a new zanpakuto. His reiatsu is purple in color. His skill and control at using his spiritual energy allows him to perform a variety of abilities.
Gin Kiri (銀霧, Silver-Mist): The shape of Koga's new zanpakuto is similar to his old one, though with minor variation. It takes the form of a katana with a dull gray sheath, siver hilt-wrapping and a guard in a shape similar to the Kidō Corps' emblem, consisting of a circle with a pentagon-like shape in the center and three points protruding from the edges evenly spaced apart. Like his previous zanpakuto Ginkiri is an illusion-type Zanpakutō.
- Shikai: The release command is "Be Silent" (黙る, damaru). Ginkiri shines with bright silver light to engulf a considerable radius, affecting any and all targets within it.
- Shikai Special Ability: Gin Kiri has several abilities in it's shikai form.
- Spiritual Threads: Kōga is able to form invisible spiritual threads to bind his opponent in place. By concentrating his spiritual energy from himself into the blade he is able to give these threads physical form as well, making them all the more deadlier. By releasing these transparent threads of energy, he can cut enemies from a distance. These threads are powerful, being able to cut an gillian class menos in half.
- Kiri no Gensō (霧の幻想 , Mist Illusion): When the sword is released, Koga is able to transform the blade of his zanpakuto into mist, if this mist is able to connect with the opponent in anyway, be it by inhaling or simply touching the opponents skin, it directly effects the opponents nervous system, allowing him to control their perception of reality. By channeling his spiritual energy into the mist, Kōga is able to distort the target's perception, effectively making a person's five senses unable to properly register what is happening.
- Kami Gensō (紙幻想, Paper Illusion): He uses this ability to trap the victim in a dark empty space where their body is made of paper that burns from toe to head while the user is watching. The purpose of this is to use the target's vision of their new form to reduce their dexterity, making it harder for the victim to battle.
- Hane no Sakushi (羽の錯視, Feather Illusion): He uses this ability to pierces the enemy's body with large illusionary black feathers, rendering them paralyzed. This allows him to cause paralysis to an opponent for a limited amount of time, as he is able to cause severe damge to the opponent during that amount of time.
- Suimin Sakushi (睡眠錯視, Sleep Illusion): This ability causes everyone within a specific area to fall into a deep sleep. From the target's point of view, it seems as if a beam of light is falling from the sky, which serves as a distraction to allow the ability to take effect. The downside, however, is that any experienced opponent have more than enough time to dispel it. This ability is used on large number of groups.
- Sakura Kiri (桜霧 , Cherry Blossom Mist): Not Yet Revealed.