Azuma is a tall, light-skinned young man of average build with neck-length black hair. He has black eyes with pronounced tear-troughs and a big, straight nose.
In his trion body he wears a navy blue, long-sleeved jacket with black lines bordering the zipper and the high collar, which he keeps open, and running horizontally around it both on the inside and the outside. Vertical black stripes run from the collar to the wrists of the jacket, interrupted only where Border's logo is emblazoned on the outer side of each sleeve a little below the wearer's shoulders. On the right breast are two piped patch pockets closed by flaps, while on the left is the B-rank logo. Underneath the jacket is a light-colored shirt with a slit collar with three holes on each side of the slit through which passes a lace tied into a loose bow. The uniform is completed by a pair of black pants and dark gray boots.
Azuma is a very self-possessed individual. Though he may show emotion in dire combat situations, he is able to retain the lucidity and analytical mind which have earned him the trust and respect of many a Border agent. He has mentored several members of the organization, some of whom know him to be slier than the widespread image of him as a person incapable of underhanded tricks. After transmitting his teachings he mostly lets his students find answers on their own, limiting himself to asking questions, taking the in rank battles only after his disciples have suggested a course of action and only rarely stating his preference.
Albeit pragmatic, Azuma is a genial person who can often be seen wearing a faint smile on his face. He is quite popular among agents, occasionally treating some to meals. He showed himself to be reassuring and slightly humorous when he told Chika Amatori not to worry about shooting through the base's wall while trying out Ibis.
(To Chika Amatori) "Get up. It's okay. It was a training accident."
(To his allies against Lamvanein) "There's a huge gap in firepower. Don't attack if you don't have to. If we rush into a shooting match, the sheer difference in firepower will wipe us out."
(To his allies against Lamvanein) "It's time to capitalize on our numerical advantage. Split up and diffuse his attention. If you stick together, one blast will take you all out."
(Commentating during rank battles) "They factored their inability to beat Arafune Unit in a long-range battle into their overall strategy. By choosing this stage and giving Arafune Unit an obvious advantage they created a natural allegiance with Suwa Unit. Tamakoma Second put a lot of thought into this urban battle." 
(Commentating during rank battles) "This match is over. Tamakoma wins."
(Commentating during rank battles) "Since Kodera explained everything, I have nothing left to say."
(To Noboru Koarai and Tsuneyuki Okudera) "I see where your opinions differ. Now, tell me where you agree."
(To Koarai and Okudera) "Go ahead, give me any job to do. I'm a pawn after all. But in this pawn's opinion, I'd prefer a simpler map."
(Azuma's motto, taken up by Koarai and Okudera) "When you fight with strategy, take into account the enemy's strategic prowess."
(To Koarai and Okudera) "Four more days. Let's make this into a winning battle."
(To Koarai and Okudera) "You two properly judged the state of battle this round. As Attackers, you've had to rely on team plays and combos up to now, but I'm thinking it's time to open up Sub Triggers to both of you."
(To Osamu Mikumo) "Hatohara hit only a person one time. Her shots never missed the mark otherwise. She underwent intense training so she'd never hit anyone again."
(To Osamu) "It's barely been a month since you stood up at that press conference and made your fiery declaration about making it onto the away mission. I never expected your squad would actually have the stuff to prove you right."
"The guy couldn't care less about himself. All he's concerned about is supporting everyone else... He's unbalanced that way..."
↑Daisuke Ashihara: Q122: Azuma has an excessively large number of disciples, but is Satori’s mentor Azuma too? A: Satori is an intuitive type so he’s not Azuma’s disciple, but he often gets treated to meals by him. Source: Border Briefing File, Question 122
↑Daisuke Ashihara: Q: Is there anyone of 18 and above who has a driver’s license for a car or a bike? A: Aside from Reiji who has already driven in the story, it seems Fuyushima, Azuma, Suwa, Tsutsumi, Kako, and Kakizaki have normal driver’s licenses. The top brass and Sawamura have licenses too. Tachikawa doesn’t as you might expect. Zoe has a motorbike license, and Kage and Tōma have motorized bicycle licenses. It seems Arafune and Hokari want motorbike licenses too. Source: Question Corner 15, Volume 20