Aida

Aida is a Shinigami of the Third Division during the tenure of Shūsuke Amagai as the Division's captain.

Appearance
Aida has brown slick hair that is combed to the right. He has black colored eyes and has a long nose that is centered in the middle of his face.

The New Captain Shūsuke Amagai arc (anime only)
After having been led by Lieutenant Izuru Kira for a while, when the Third Division is informed that they will be receiving a new Captain, it causes quite a stir at the barracks. Both Inose and Aida agree that they have never heard of Shūsuke Amagai before, but Aida admits that since the announcement, he has heard rumors that Amagai was previously part of the Patrol Corps before being promoted to the position of captain within the Gotei 13. When Inose expresses his dislike of the idea that they now have a captain whom they've never met, Aida reminds him that they still have Izuru as their lieutenant. However, when Izuru arrives and shows an optimistic attitude for the arrival of Amagai, they both seem annoyed by this.

When Amagai arrives with Makoto Kibune, Aida and Inose discuss his appearance whilst he is in the middle of a conversation with Izuru. When Amagai notices their expressions and questions them, Aida is shocked when Inose immediately steps forward, and declares that the Third Division has done fine up until now with a captain. When Izuru moves to admonish him, Amagai shocks them all by preventing him from doing so, showing a large amount of empathy for their situation. He understands that having somebody they haven't met just suddenly become the head of their squad must be a difficult situation for them to get used to, but promises that he will do everything in his power to protect them.

Later, Izuru decides that the Third Division will hold a party for their new officers, Amagai and Kibune, to welcome them. However, he doesn't realize that Amagai has a low tolerance for alcohol, and the new captain immediately passes out, much to Izuru's dismay. Aida and Inose offer to tidy up given the captain's condition but Kibune declines the offer, still intent on capitalizing on the situation by getting to know the Shinigami around him to prepare himself for his new role as their 3rd Seat officer. Aida and Inose watch him do this, before Aida wonders what they should do regarding Amagai. Inose maintains his original view that they don't need a new captain. Aida sighs before agreeing.

Suddenly, an emergency is announced throughout the Seireitei, with thirty Menos Grande appearing in the Dangai world. Not knowing about Amagai's current condition, Genryusai Shigekuni Yamamoto orders that the Third Division should enter the Dangai and immediately deal with the threat. At first Izuru is hesitant by Kibune convinces him to lead the squad in the attack. Izuru finally agrees, oragnizing his squad and telling the members to split up into groups of four per enemy in order to carry out their mission before entering the Dangai.

When they confront the Menos, the Third Division attack decisively, defeating five of the Menos without much trouble. However, for inexplicable reasons, the Kōryū suddenly switches back on, surprising the entire division, including Aida who wonders what is happening and why the current has activated. Suddenly a Kōtotsu also appears, forcing Izuru to order a retreat after Kibune states that he definitely orders both of them to be shut down so that could safely enter the Dangai.

Suddenly Amagai shows up, leaping over his underlings to control the Kōtotsu and protect them. At first Izuru tells him to run but Kibune advises them all to watch closely and witness the power of their new captain. Insisting that he is keeping his promise, Amagai destroys the Kōtotsu, much to the surprise of everyone in the division, leaving everyone to stare at him in an awestruck fashion. After Amagai asks if anyone is injured, Inose comments on his prowess and Aida agrees with him. However, Amagai soon collapses, revealing that he is still inhibited by the alcohol, making everyone wonder how he managed to defeat the Kōtotsu whilst drunk.