Akira Nikaidou

Born on December 11. Blood Type B. 175 cm tall (approx. 5'7"). 57 kg (approx. 125 lbs).

Akira is the 16-year-old protagonist of the series in his second year of High School. He is strong and impatient, often skipping class since he does not like school, claiming that it is boring. However, although he skips classes often, he still manages to get into the top 5 positions in the school.

Changing into his shadow form causes his hair to turn black, his clothing to change, and his eyes to turn red. In order for Akira to stay in his human form, in the manga he depends on Shirogane to be his shadow, while in the anime, he eventually uses a doppler item. While in his spirit form, at first he uses a pair of daggers to fight, but later in the series they change to a more complex and larger set of blades.

Although it is said that he is of the royal line of the light, hence a Rei, the truth is that he is Ryuko's successor. At present, Akira has yet to awaken, and hence is unable to regain his memories for when he was king. However, he has awoken once before, during the time he and Kengo first met Kou, taking his Rei form to subdue and defeat Kengo, at the same time stopping Kou from doing a suicide attack. Because Ryuko had not fully regained his strength, he was unable to retain that form and reverted back into Akira, who collapsed from exhaustion. Akira's memory of that event was erased by Kou along with Kengo's because he felt that the incident was too much to handle for the both of them, but Akira has recently regained that memory.

(Source: Wikipedia)