Akira is the first member of the Shiseiten to appear in the story. He was a peasant boy whom Kyo found in a village that he'd completely destroyed. Though Akira was very young and the only survivor, he refused to cry and instead faced Kyo with the intention of fighting him. Kyo was impressed with Akira's fighting spirit and adopted him, promising to make him the strongest man in the world - after Kyo, of course. He was nicknamed the Soutou no Ryuu for two reasons: one, because his techniques require two swords, called Chisakatana, and two, because of his two personalities. One moment he is docile, kind, and gentle, and in a flash, he is a blood-thirsty killer akin to Kyo himself.

Akira was incapable of unlocking his full potential because he didn't have samurai/noble blood, but he overcame this limitation by intentionally blinding himself. He gained the "eye of the heart", making him even more perceptive than those who can see. In a ruse to gain Kyo's body, Akira temporarily joined Nobunaga's warriors by killing Ajira, the servant of Nobunaga. Because of this, Akira was allowed to adopt Ajira's name. After Akira betrayed Nobunaga, he joined Kyo again after Okuni gave him her hair.

His signature move is the Muhyo Gehetten, which traps his enemies in a pillar of ice and shatters them. Another attack he uses is the Hyoken Seiso. This technique traps his enemies in a large hollow mountain of ice. While issuing this attack, Akira is invulnerable to attacks and can torture his enemies until they die, or he can kill them in an instant. His ultimate attack involves the Inferno's Chill and Hyoma Juji Soumai. The Inferno's Chill drops the tempurature to below Absolute Zero. Akira can then focus the Inferno's Chill into his swords and direct an attack, the Hyoma Juji Soumai, at his enemies, killing them instantly. During his fight against Tokito, he was able to surpass his limited power by using his Inferno's Chill on himself, making him more powerful, and use a new technique called "Shadow Ice of Maria". This power was limited and caused Akira's body damage.