Born on December 11, Akira has blood type B, stands at approximately 175 cm (5'7"), and weighs around 57 kg (125 lbs). At 16 years old, he is a second-year high school student and the protagonist of the series. Known for his strength and impatience, Akira often skips classes, finding school boring. Despite his frequent absences, he still manages to rank among the top five students in his school.
When transforming into his shadow form, Akira's hair turns black, his clothing changes, and his eyes become red. In the manga, he relies on Shirogane to act as his shadow to maintain his human form, while in the anime, he eventually uses a doppler item. Initially, he fights using a pair of daggers, but later in the series, these evolve into a more complex and larger set of blades.
Akira is said to be of the royal line of light, making him a Rei. However, the truth is that he is Ryuko's successor. Currently, Akira has yet to fully awaken and thus cannot regain his memories from when he was king. He did awaken once before, during his first encounter with Kou and Kengo, where he took his Rei form to defeat Kengo and prevent Kou from committing a suicide attack. Since Ryuko had not fully regained his strength, he reverted back to Akira, who collapsed from exhaustion. Kou erased both Akira's and Kengo's memories of this event, believing it was too much for them to handle. However, Akira has recently started to recover those memories.
