First appearance: Battle 167
Age: 29-30
Type: Sei
Type: Satsujin Ken
Yami Symbol: Sky
Martial Art: Karate (specializes in Shinchi Nengen style)

Hongou Akira is a member of Yami's One Shadow Nine Fists, he is a master that utilizes Karate, he was the master of Kanou Shou (who died after being defeated by Kenichi during the D of D tournament). He scorns on using science and technology as tools to measure one's level of martial arts, but does not hesitate to raise the obstacles and difficulty level for Shou when he was in an experiment. Evidence showed that though he was extremely hard on Shou, it was because he wanted to dispel the doubts of several other people including the One Shadow that Shou had the right to be the 'Sole Successor'. Thus, he was a stern and cold teacher to Shou so that the disciple would never lose a match, which might discredit his and Shou's reputation. However he let Shou do as he pleased sometimes, including keeping a little bird and riding on him for a while on boat.

Hongou is a rather serious man when it comes to many things, even as simple as meeting the other Fists. Even when taking simple kind gestures from others such as Lona thanking him, he did not talk and just stared sternly. He's also a very quiet person, as he rarely speaks unless he wishes to, especially in battle. He scorns the use of science and technology to measure one's level of Martial Arts, though he has shown he doesn't mind using it to train Shou. Despite his cold nature, he has a rather close bond to his disciple and cares for him deeply, as their relationship is like that of a father-son like relationship. He has faith in Shou that he is the 'Sole Successor' and wishes to disapprove everyone's opinion of Shou that he is not worthy of the title. He has also shown visible rage when he heard Shou died during the D of D Tournament and even mourned the loss over his beloved disciple.

He harbors a great hatred for Ryozanpaku, as it is revealed that he received his scar from Sakaki Shio and is clearly upset when he learns Shou died saving Fuurinji Miu. In the battle for the Karate successor of Yami, he tells Kenichi to tell Sakaki that they will "end this soon."

When he was still friends with Sakaki, Hongou was seemingly more soft-hearted and spoke more than he does now. He also seemed to have been down the path of the Katsujin Ken since he helped saved several people from getting killed on more than one occasion such as how he leaped in front of some bullets just so the hostages wouldn't get hurt.

Hongou's reason for embracing the Satsujin Ken is out of honor for Suzuki Hajime, who demanded a death match with him when Yami pitted Sakaki, Hajime, and him in a death match for the succession of Karate in Yami. His conflict with Sakaki stems from this reason: whereas Sakaki wanted to let Hajime live and do what was best for him, Hongou was more concerned with fulfilling Hajime's wishes, calling Sakaki "selfish" for refusing to understand that.

While he shows to be ruthless and very serious most the time, he, compared to the other members of Yami, has proven to be very honorable. He stopped his fight with Sakaki and assisted him in trying to save Miu from Jenazad when Jenazad interfered and even promised the Elder that he would return her to her home. Even Sakaki vouches that he is a man who keeps his word. He also has a high respect for the Kuremisago clan, stating that he couldn't bring himself to shed blood on their sacred land. He also wishes for no disciples to lose their lives in battle, such as stating to Sakaki that he wishes for Kenichi and Miu not to die in their fights with Jenazad's men, showing a more compassionate side.