Where Demon Avengers originated I think I know where Nexon got their idea from now... There's no subtitles btw and skip to 1:20 ish the Demon avenger bit only lasts for 20 seconds. Story info (for those who want to know): There is this girl looking for his boyfriend and his boyfriend is controlled by a "Black Mage" demon person. After they fight he killed her kind of and he awakened saying he wants to avenge her. This series was created in 2010 and is the second season ep 1.