Orphaned at a young age, Moriya is taken in my Gaisei, just like Yuki and Kaede. However, those two had pure souls. Moriya's soul had already been effected by the violence around him. When the Gate of Hell began to open, Moriya quickly became evil. First, he kills his master in cold blood, then begins to track down the Four Guardians under Kagami's orders.

The third of the orphans raised by Gaisei. She is quite gentle, disliking the ways of war and violence. However, when Gaisei is killed by Moriya, she quickly learns to fight with a Naganita, a long spear-like weapon. Yuki joins Kaede on his quest so that she can return to her peaceful life.

He who slices life. Setsuna is actually a demonic spirit that escaped from the Gate of Hell. Upon arrival on Earth, he resurrected the body of a six month old baby and took it as his own. Less than 6 months later, Setsuna is fully grown and begins traveling the world to find mortals to slaughter. He wields a blade glowing with dark power.

A soldier in a mercenary group. She is actually a woman by the name of Kaori. When her brother, Kojiroh, is killed under mysterious circumstances, she takes his name and his position to find his killers.

A high ranking officer in the same mercenary band as Kojiroh. He knows about her true identity and has been a mentor and friend to her. Although he is usually compassionate to others, he follows his orders flawlessly.

Shikyo joined the mercenary troop of Washizuka. However, this madman never intended to do honest work, he simply desired to kill. After killing hundreds of mercenaries in their sleep, Washizuka executes the insane man. However, he is then resurrected by the dark energy of the Gate of Hell. He becomes a zombie-like creature with the same mission as it had in life. The only real difference between the two is that only Mukuro has the elemental strength to darkness and the weakness to holy. Shikyo does not. Mukuro means corpse in Japanese.

A Chinese monk sent to Japan to ensure that the Gate of Hell remains closed. Recca Lee is serious to a fault and would never give up his mission until his own death. Lee fights almost exclusively with his kicks, but does have an iron fan as well.

Zantetsu is a ninja of the old arts. He is the last of his kind. He has grown quite old, being in his late 50s. He journeys the world looking for his last challenge before taking his own life, and sending his twin daggers, Flow and Shadow, to his grandson to carry on the family legacy.

Amano Hyo fancies himself as a lady's man, as well as the supreme warrior. He tends to be over dramatic. Amano visits Hibiki's home to have his broken blade reforged, but he finds Takane, the master weaponsmith dead and his daughter gone to avenge the family. He decides to follow her to give Hibiki any help he can. He wields a bamboo sword that gives off Sakura Cherry Blossoms with each strike. Chess references are all related to a similar game in Japan.

The daughter of a Shinto priest. Akari is very happy-go-lucky; she journeys simply to see the world. However, she is also searching for a cure to her sister's aliment. Accompanied by Juzoh and a host of demons she converted to goodness, Akari is hard to defeat. She fights with a Shinto blessing rod (a stick with little paper talisman things hanging on the end).

Juzoh was orphaned at a young age. He has lived in the Ichijo home since before Akari was even born. Thus, Juzoh is very much like Akari's older brother and he is often taken along on her misadventures. When Akari runs off to see the Gate of Hell, Juzoh follows her, both to protect her and also to cure Hikari, Akari's older sister who is Juzoh's age. While he feels brotherly love for Akari, he burns with passion for Hikari.

The avatar of the Red Phoenix Suzaku. Kagami is ancient, far older than any person should be alive. His task was to assure that the Gate of Hell never opened. However, he grew bored of his task and eventually the evil of the gate itself crept into his heart, causing him to choose destruction over his mission. He is the first to try to open the Gate and release demons into the world.

Genbu Okina is the avatar of Genbu the Dragon-Turtle. Okina is the oldest of all the avatars, being several hundred years old. After Moriya kills Gaisei, Okina helps to complete both Kaede and Yuki's training. This old man loves fishing and is friend to many turtles.

Shigen is the avatar of the white tiger, Byakko. Once trapped inside stone, Shigen was freed by Kagami, who used dark magics to control Shigen. Now freed of Kagami's control, Shigen begins to live a normal life, even adopting a daughter. However, with the re-emergence of the Gate of Hell, he is called into service again and unwilling to leave his daughter, Kotetsu, alone, he brings her with. Kotestu is the kid in the red clothing.

Musashi is THE Musashi, the incredible Japanese swordsman of long ago. Unfortunately, he died long ago, too. Kagami has resurrected the legendary swordsman for his own vile purposes.