Kaien Shiba

"Kaien values friendship above everything else. His spirit of kindness lingers on today." - picture caption by Tite Kubo

was the lieutenant of the 13th Division, under Jūshirō Ukitake, up until his death at the hands of a Hollow that also killed his wife, Miyako Shiba.

Personality
Kaien was an upbeat and kind young man from the Shiba house, tattooing his arm with the Shiba house symbol, who treated all his subordinates equally. He made friends very easily, earning the respect and trust of most fellow Shinigami with not only with his above-average combat prowess but mainly with his kind and honest nature. He especially treasures bonds with others, believing that "heart" exists in them and remains with people's comrades after people die, and as such, believes that people must not die alone.

It is known that his favorite food was ohagi, and he liked to take afternoon nap if he could.

Appearance
Kaien closely resembles Ichigo Kurosaki in both appearance and personality, and their resemblance is brought up multiple times in the series. While Rukia was training Ichigo she often became exasperated by his lack of understanding of things Kaien would have known, and Ukitake is stunned by Ichigo's appearance. Byakuya Kuchiki also notes the resemblance, even stating that Ichigo's attitude annoyed him as Kaien's had.

Strangely Kaien's siblings, Ganju and Kūkaku, do not remark upon or even openly notice Ichigo's resemblance to Kaien.

As of yet Ichigo is unaware of his resemblance to the late Kaien, but may know something about Rukia's relationship with him; when looking for Rukia, he knows she could only be at the Shiba manor after realizing that she is not in the Seireitei.

History
He was a father/older brother figure to Rukia Kuchiki, whom he taught how to fight and helped her find a place within the 13th Division. He was also a prodigy amongst Shinigami; graduating from a six year curriculum in just one year and becoming a lieutenant five years after, around the time Ichimaru Gin killed the 5th division 3rd seat. He was also married to another shinigami, the 3rd Seat of his division, Miyako. One day, however, Miyako was possessed by a Hollow called Metastacia and killed her subordinates, leading Kaien to fight the Hollow in an attempt to avenge her. Kaien, however, would be controlled by the Hollow as well, leading him to almost attack Rukia. Although Ukitake attempted to save her, his disease prevented this. He then charged Rukia, who had come back because, as she thought, she would otherwise have been ashamed of her cowardice. Ukitake then urges Rukia to kill him, as he is no longer himself. In the manga, Rukia stabs Kaien as he leaps at her, while in the anime, he appears to fall on her sword (which she is holding upright, rather than at her side in the manga). Before dying, he thanks Ukitake for allowing him to fight for the sake of his honor, apologizes to Rukia for forcing her into that situation and thanks her for allowing his heart to remain behind.

Since his death, the 13th Division has not assigned another lieutenant, and instead is run by two 3rd Seats, Sentarō Kotsubaki and Kiyone Kotetsu. Both of Kaien's siblings, Kūkaku and Ganju, became distrustful of Shinigami. At some point, the Shiba clan fell from its status as a noble clan for an unspecified later. Rukia, who felt the most responsible for Kaien's death, carried a heavy amount of guilt over his death until many years later, when she finally brought herself to apologize to Kaien's siblings. It is later revealed that due to the Hollow's special ability, Kaien and the Hollow were taken to the Hueco Mundo, where the Hollow Aaroniero Arruruerie ate them both and took both their abilities.

Hueco Mundo arc
After Rukia separated from her companions she encountered the Arrancar Aaroniero Arruruerie, who upon removing his mask is immediately recognized by Rukia as Kaien. The two have a long chat but after he attacks her she begins to doubt him being Kaien. It is not until he asks her to kill her friends that Rukia realizes that he cannot be who he claims, and she begins to attack Aaroniero. Rukia learns that he has Kaien's memories, though, and that Aaroniero had absorbed Metastacia, and Kaien's spirit body along with it, and is unable to fight him. After recalling Kaien's teachings about the heart and using a technique that he did not remember teaching her, Rukia was finally able to bring peace to Kaien's soul.

Powers & Abilities
Swordsmanship Specialist: Kaien was a skilled swordsman, evident from when he trained Rukia, and somewhat shown by Aaroniero when he was fighting Rukia based on Kaien's memories.

Flash Steps User: Kaien can use flash steps, which he did to cut off a couple of Metastacia's arms, taking the Hollow by surprise.

Kidō Practitioner: Even when disarmed in combat, Kaien has shown that he could still fight via the use of Kidō.

Zanpakutō



 * Shikai: Its Shikai command is . Nejibana's shikai is represented as a cross between a trident and a ji (a Chinese halberd) with a crystalline appearance that has the ability to manipulate water. Like the ji, it bears a horsehair tassel, although it is blue instead of the traditional red; similarly the two side blades are straight with concave edges as opposed to the usual crescent blade.


 * Shikai Special Ability: Nejibana's ability consists in use the shockwaves, it creates in conjunction with trident attacks to "crush and split the enemy in two." Kaien's techniques and form are also revealed during the battle, and are described by Rukia as "a trident technique reminiscent of dancing."


 * Bankai: Not Achieved

Trivia

 * Because of their strong resemblance to each other, many fans even assumed that Ichigo was Kaien's reincarnation or at the very least his cousin until the Hueco Mundo arc.