|Dub Name||Devin Aeron|
|Game Debut||Danball Senki (PSP)|
|Anime Debut||Episode 01|
|Appears in||Game, Anime|
|Voice Actor||Takanori Hoshino|
|Relatives|| Keiko Yagami (deceased wife)|
Yuki Yagami (deceased daughter)
|Occupation|| Policeman (former) |
Black Unit Commander (defected)
Prime Minister's Personal Intelligence
|Affiliation(s)|| Innovator (defected)|
Eiji has amber eyes and long, auburn hair. He has a commanding stature, and he is always seen wearing formal business attire with a red tie and a cape. Before his wife and daughter passed away, he had shorter hair.
BackgroundOnce a happy working police officer with a wife and daughter, Eiji Yagami's life changed when his family died in the Tokio Bridge Collapse Incident. Very upset and confused by the event, he was approached by Yoshimitsu Kaidou who was visiting the deceased victims' families. Seeing usefulness within him, Kaidou offers him a job under the false pretenses of helping to prevent such an event from ever occurring again.
In the first two episodes, Yagami discovers that the AX-00 armor has gone missing and orders the three agents to search for it. Back at the Innovator base, he attempts to convince an man that their mission is necessary for humanity’s future.
After his agents fail in their mission, the scientist tells him that the Death Lock system would release a poison dart that could kill the culprit and the chip inside the capsule would also self-destruct. Yagami is shocked that the scientist planned these events ahead of time, but regains his compourse, claiming that they can win a battle against Ban Yamano. The scientist asks him if he's sure that'll win, but Yagami orders the agents to take him back to his cell.
Yagami discusses the scientist's current condition with a Innovator superior, promising that he'll eventually understand their ideals. In the meantime, he concocts a new LBX to destroy the AX-00, codenamed Egypt.
Yagami’s new operation executes according to plan: his agents were able to use Egypt to mentally brainwash Kazuya into craving a desire to destroy Achilles. As Achilles reached below 25% during the battle, Yagami’s plan was assured until an unknown quantity changed the battle: V Mode. As Achilles destroys Egypt, he watches in horror as he decides to retrieve the Platinum Capsule quicker than before.
Eiji discovers that Assassin’s data was used from the Innovators data and questions his boss if he ordered the assassination attempt on Prime Minister Sousuke Zaizen based on Yoshimitsu’s governmental position. Believing the Innovators’ ideals to be above such terrorist like behavior, only for Kaidou to advise him not to jump to conclusions and their justice as an Innovator was never changed. When Kaidou tells him his lack of knowledge about the assassination, Eiji decides to believe him. Kaidou asks him about the recapturing of the Platinum Capsule, and he informs Kaidou that his next plan is commencing.
Later on, however, Eiji learns of Yoshimitsu's true objectives, so he decides to defect and join the Seeker 's cause to foil Yoshimitsu Kaidou's plans and to gain redemption. In episode 24, he angrily marches into Kaidou’s office, demanding him to explain the attack on Artemis stadium and the chaos that resulted in the death of four officers’ live. Yoshimitsu replies that he should be grateful for contributions, to which Yagami retorts that his boss is only obsessed with power, fully aware that Kaidou will sink himself to any levels to achieve his goals. Kaidou immediately fires him from the Innovator, claiming that there others willing to take his position, and so he storms off, unaware of the events that inspired after he left.
During his final day at the Innovator base, he is immediately targeted by security after "Kaidou' and Sadamatsu agree that his information gathering equals betraying the Innovators. In episode, 27, Eiji returns to the Innovator’s bases and downloads all the necessary files regarding the Tokio Bridge Collapse Incident, only to be caught by the Red Brigade. Fleeing with his assistant and supporter, they eventually find a room to hide in. However, his assistant betrays him in order to gain Yagami’s position as the leader of the Black Intelligence Division, where he is tuck until an unexpected rescue from Jin Kaidou, who opens the door and tell him to keep going. On his way out, Eiji finds Rina Ishimori, distraught. He tells her whatever she did happened, and right now it is imperative that they escape. She complies, and the two reach the cargo bay joined by this Triple Agents, who unveil the new ship, The Eclipse. They make their escape before the Red Brigade can catch up to them.
He returns in episode thirty six, saving Ban Yamano and his friends from the Innvoator’s henchman and fights off one with Takuya Uzaki. A confused Ban and angry Takuya want him to explain why a (former) member of Innovator would help them. After explaining that he learned the truth about Kaidou and wants to defeat his corruption, they allow him and the agents to meet with Yuusuke at Tiny Orbit, where the Uzaki brothers cast suspicions about their trust in him.
During the siege on Tiny Orbit, he defends the fourth floor with the agents. Eventually, Kazu, Ami, and Gouda join him to defend the research lab as they finish the Eternal Cyber.
After the events with the Innovator incident, he turns himself in only to be scouted by Prime Minister Sousuke Zaizen to be his personal intelligence as a plea-bargain for his investigation skills.