Sentarō Kotsubaki

is the co-3rd seat/acting lieutenant of the Thirteenth Division of the Gotei 13. He constantly argues with other co-third seat, Kiyone Kotetsu. Like Kiyone, he shows a great deal of admiration towards his assigned Captain, Jūshirō Ukitake.

Character Outline
Sentarō dresses a bit differently from standard Shinigami, wearing a white headband and white shoulder straps, both apparently made from the same material. However, 50 years before the main storyline, Sentarō and Kiyone both dressed closer to the standard Shinigami uniform.

Sentarō, like Kiyone Kotetsu, holds his captain in high regard and tries to impress him in any way possible. Both he and Kiyone usually get in fights over their competition to impress their captain. Oddly enough, they both share the same birthday as well, which further fuels their rivalry.

History
Not much is known about Sentarō's history, except that he came from Rukongai. He was already a member of the 13th Division by the time Rukia Kuchiki joined. Both he and Kiyone would occasionally show up on duty drunk, as noted by Lieutenant Kaien Shiba (who was frequently annoyed when they did so). It is unknown what rank Sentarō had when both Kaien and Miyako were still alive, but he (and Kiyone) became a 3rd Seat officer sometime before the main storyline.

Soul Society arc
Sentarō first appeared alongside his partner Kiyone Kotetsu when they inform Captain Jūshirō Ukitake about Sōsuke Aizen's apparent death. Both Sentarō and Kiyone decide to take the blame for delaying the message to Ukitake, since he was sick. Later, both he and Kiyone follow Ukitake when he stops Byakuya Kuchiki from killing Hanatarō Yamada and Ganju Shiba. They do not show themselves until after Byakuya leaves. Ukitake orders Sentarō to take Rukia Kuchiki back to her cell, while Kiyone gets a Fourth Division medic to treat Ganju's wounds. When Hanatarō tries to stop him, Sentarō admits that he does not want to put her back in her cell, but states that he has to follow orders.

Later, Sentarō and Kiyone bring Hanatarō to Retsu Unohana, and Sentarō gives her a report that states that Hanatarō was forced to help the Ryoka, but Unohana still punishes him, despite this.

When Ukitake's appeals to the Central 46 fails, and the execution date is moved, he decides to save Rukia himself, and Sentarō and Kiyone decide to assist him. They arrive at Sōkyoku Hill, and Ukitake, along with Shunsui Kyōraku, destroys the Sōkyoku. After Renji Abarai escapes with Rukia, and after Ichigo Kurosaki begins battling Byakuya, Kiyone tries to help her sister, and Sentarō tries to stop her, but he is knocked unconscious by Suì-Fēng, who also begins to kill Kiyone after Genryūsai Shigekuni Yamamoto leaves to follow a fleeing Ukitake and Kyōraku (who stated it was better to fight elsewhere, so the others wouldn't get caught in the crossfire). They are ultimately saved by Yoruichi Shihōin, who drags Suì-Fēng away to do battle elsewhere.

After the danger around them is passed, Unohana takes Sentarō and everyone else wounded at Sōkyoku Hill (except for those who are still fighting) to the 4th Division to be treated. Later, while Sentarō is in recovery, he receives Isane Kotetsu's message elaborating on Aizen's betrayal.

Bount Arc (anime only)
Sentarō is present when Ukitake announces to the members of the Division that all communication between Soul Society and the Human World is to be stopped temporarily and that the Senkaimon is to be closed. In the SRDI, Ukitake summons Sentarō and tells him that the survey is complete. He instructs Sentarō to report this news to the necessary people and Sentarō leaves. When the Bount invade Soul Society, Sentarō and Kiyone lead a group of Shinigami to Rukongai's 43rd district to aid Rukia.

Kiyone and Sentarō hear via Hell Butterfly about that Bount's objective is a number of devices called Jōkaishō. They are told that the Hell Butterflies will aid them in searching for the devices. Acting on Ukitake's order, Sentarō breaks open a floor to reveal one of the Jōkaishō. Kiyone and Sentarō then begin sealing it up.

Fake Karakura Town arc
After Aizen is captured, Sentarō is seen eavesdropping alongside Ukitake and Kiyone on Yamamoto scolding Shunsui, Byakuya, and Kenpachi for losing their respective captain haori. Ukitake notes that 10 days have past since the battle, Yamamoto has lost his left arm but it looks like his stamina has returned, which is a relief as Soul Society still has yet to see a being capable of replacing the man.

Zanpakutō Unknown Tales arc (anime only)
Sentarō was there alongside his captain Jūshirō Ukitake when the renegade Zanpakutō spirit, Muramasa, declares war against the Shinigami of Soul Society. He along with partner Kiyone Kotetsu scramble away from the area as they and the other Shinigami are surprised attacked by renegade Zanpakutō spirit.

Gotei 13 Invading Army arc (anime only)
When Ichigo arrives in Soul Society, Sentarō assists in his arrest, along with other senior Shinigami.

Powers & Abilities
Shunpo: While not seen often, Sentarō showed enough skill in Shunpo to appear immediately to not keep his captain waiting.

Zanpakutō

 * Shikai: Not Yet Revealed
 * Bankai: Not Yet Achieved

Quotes

 * (To Jūshirō Ukitake) "I'm very, very sorry, but I respect captain too much and I couldn't help but follow captain anywhere he goes."

Navigation
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