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.

When the Third Division are on a mission to find a noble's cat, Aida helps to direct his fellow Shinigami from one of the rooftops so that they can close in on completing their mission. When Izuru almost catches the cat, but falls, Kibune appears and stops the cat from escaping. Inose congratulates their new officer while Aida informs Izuru that he was trying too hard and that's why he failed to catch the cat without slipping. At Kibune's request, Izuru confirms that the cat in his hands is the one they are searching for, thus their mission is complete.

Inose proceeds to complain that the mission isn't a very important one, and thus demeaning, Aida reinforces this opinion by stating they had also had the unimportant job of guarding a material shop as well on the previous day. He then moves on to express his dissatisfaction that all of their missions have been uninspiring recently. Kibune calms the situation down before inviting them out for a drink, which both Inose and Aida enthusiastically agree to, although Izuru insists he has work to do. They have a good time together over at the Kamenoya Bar, drinking sake and bonding as a unit without Izuru.

The next day, Amagai decides to hold a new type of training session with the Third Division. He gives everyone a colored headband so that the color he calls out will become the enemy and they will coordinate as teams and surround them. Aida ends up wearing a pink headband for the exercise. Izuru is left on the side as he has never lead this type of training, which Kibune has experience with, having worked with Amagai for a while. The division responds well to the directions given to them by both Amagai and Kibune, shocking Izuru with their teamwork.

After training, while cleaning up, both Aida and Inose discuss the session and their admiration for both Amagai and Kibune. Aida expresses his excitement that the division has proven that they can do great things if they work together as a team. He also insists that Kibune is more reliable that Izuru at that point in time, but admonishes Inose for wondering if Kibune would replace Izuru as their new lieutenant in the future. Neither of them are aware that Izuru is close by listening to their conversation.

Later that evening, Izuru and Kibune get trapped down an old execution pit with a new recruit called Shinta Seko. Aida is among the Shinigami who arrive with Amagai to help them out of the situation. Aida informs Amagai that Shinta has been taken to the Fourth Division infirmary. He also insists, however, that they are also unsure that they will be able to save the young Shinigami as his injuries are very extensive. Aida also reports that the ground above the execution pit appears to have been rigged to collapse with their weight, which shocks Izuru, who becomes even more suspicious of Kibune.

Sometime later, the Third Division groups up in an old Assembly area where Kibune had asked special permission for the all to train. Aida comments that the area is very rarely used these days so, to some recruits, its existence is only a rumor. When Izuru and Kibune arrive they ask where their captain and they explain that Amagai is requesting new measures for multiple squad training sessions. They later learn that the proposal was temporarily rejected, much to their disappointment. Aida and Kanō complain that now they aren't going to get much respect and that their menial chores for the other squads will continue.

Aida complains about having to clean the bathroom of the Seventh Division. Both Aida and Kanō agree that whilst their experiences are demeaning, they still feel better than the Fourth Division, who practically exist to do the chores of others. They then notice that Inose is looking very uncomfortable with this statement and soon realize that he had been previously made to do their laundry, which causes them all to feel quite crestfallen and useless in that moment. Even Izuru feels bad.

Kiibune arrives and informs them that both Shunsui Kyōraku and Jūshirō Ukitake liked Amagai's idea. When Izuru confronts him about entering the Kasumiōji Noble Family complex, he denies it using the logic that a lowly Shinigami would not be allowed to enter the complex. The other Shinigami of the division agree with him. An emergency is soon announced, and while everyone is eager to get out and prove their worth, Izuru insists on waiting for Amagai to return. Aida disagrees strongly and wants to get out there, telling Kibune that he would rather follow him. They all agree to disobey Izuru's orders.

When the squad arrives at the designated area, the place is empty. Izuru follows them and insists they should return as they ave no information and were in the dark. Aida and Inose ask why he would think that when they've come so far and Kibune accuses Izuru of trying to dampen the spirits of the Third Division. The two then start bickering with Aida and Inose having to separate them to prevent a fight from breaking out. Before they fight, Amagai arrives on the scene and apologizes to them for leaving. He also admonishes Kibune for disobeying Izuru along with the others.

Menos Grande then appear in the area, and the other squads run past them all to attack, causing a great amount of confusion with low chances of maneuverability. Amagai tells the rest of the squads to follow the guidance of his Shinigami. Amagi instructs Aida to direct the Sixth Division which he does successfully to destroy a Menos. The rest of the Third Division are successful in their endeavors to help the other squads in defeating their opponents as well. The whol things is revealed to have been a ruse by Genryūsai Shigekuni Yamamoto to test what Amagai would do in such a situation with multiple squads.

Their help in the destruction of the dummy Menos helps to greatly boost the morale of those in the Third Division. Yamamoto even agrees to the joint training sessions that Amagai had previously proposed. Aida not feels that his squad now has nothing to feel ashamed about anymore due to their success. They all agree that Amagai has been a very positive influence on their squad and they are happy to have him. However, they soon realize that Amagai is still intoxicated and he passes out, much to their shock.

After Amagai agrees to join Ichigo Kurosaki in his attempt to rescue Rurichiyo Kasumiōji, who has been kidnapped, he wonders if Kibune is involved with the plot. When he arrives at the Third Division barracks, Aida, Inose and Kanō inform Amagai that Izuru has gone to the stadium. They demand to know just what is going on, but Amagai maintains that they are in a rush to get to the stadium to help Izuru and that the explanation can wait. They agree to follow him but Inose soon spots assassins fleeing with Rurichiyo. Amagai decides to follow them with Ichigo and orders Aida, Inose and Kanō to help Izuru at the stadium and they agree to do so.

They all arrive during the battle between Izuru and Kibune. Their lieutenant soon informs them that Kibune is a traitor and has been working with the Kasumiōji family this entire time as he had originally suspected. The Shinigami are confused and ask Kibune if this is true, reluctant to believe he would betray them. Kibune laughs before responding that he is going to kill them all, using his Zanpakutō, Reppū, to attack them. They barely dodge the attack alive with an injured Aida rolling down several of the rows of seats.

Kibune moves to attack again but Izuru protects them all using his own Zanpakutō. During their fight, Kibune declares that he could kill off the entire Third Division, but Izuru asks him if he even knows what friends are. Kibune references their weakness as a reason for not even daring to consider them a friend and he must destroy them. Izuru reaffirms that he will not allow him to do that. Just as Kibune starts to be devoured by his Bakkōtō, Aida awakens from his injuries, seeing the situation and wakes up the other two. They watch with bated breath as Izuru finally defeats Kibune. They rush over to him and catch him as he collapses with exhaustion.