Takeo (Kor. 타키오) is a Modified Human and one of the main series' protagonists. He is an ex-member of the DA-5, which was a special forces team of the Union. Unlike the others, he was tricked into working for the Union by Dr. Aris, who pretended to be his sister that was being held captive by the Union. He eventually found out the truth and switched sides along with Tao, joining up with Rai and Frankenstein. He currently works as a security official at Ye Ran High School and is a member of the RK-5.

Johnny Rayflo is a rich vampire playboy with a large mansion and several vampire maids. He was known in the past as "The Confined Elagabalus." Charles J. Chrishunds is his vassal. He acts as a food source for the devout Charley, who refuses to drink human blood. The two of them are constantly fighting, mostly due to Rayflo's perverse nature and tendency to refer to Charley as "Cherry."

Iga strongest shinobi. He lives to fight strong opponents. Oboro received hellish training and difficult missions for 15 years and wanted to fight Nobunaga to be known as the strongest, but Nobunaga was betrayed little before he meets him. He was hired to kill Harima, but ended serving him for 1 year, hoping he will find someone strong while travelling with him.

Shugarl is a high-ranked demon who uses a practical version of the butterfly effect to fight instead of magic. He is first introduced as a villain in the seventh chapter of the manga, but later saves Idamaria, sacrificing himself. He is smoking in most scenes. Most of Shugarl's abilities are based in his mathematical knowledge, but he may also use a derivation of magic, which allows him to summon chain blades made of demonic steel.