Devil Slayer Magic (HB)

"Darkness is now lingering inside you. I'm sure you can't feel it, as it stands, it's as good as non-existent right now, but...but, but...it will grow. Unlike the Gods of the heavens, or the Dragons of this world, Devils are not something that is supposed to exist. Our bodies are forged from two elements that are meant to be in harmony, not become one. Fire and water take each other out, but can work together, never meant to be a...combined, singular force. But the devils deny that, and so, how do you kill something that was never meant to exist? Simple, use its own power against it. The very essence and basis of all Slayer Magic. Fire with fire, and all that hub-bub."

- Azazel teaching Reitei about his Devil Slayer Magic Devil Slayer Magic (滅悪魔法, Metsuaku Mahō) is a Lost, Caster and most obviously, a Slayer Magic, utilized to slay creatures known as Devils, or Demons as they're more popularily known, beings who are associated with sins, chaos, darkness and many more negative concepts and ideas pertaining to their evil nature. Users of Devil Slayer Magic are known by the title of Exorcist Mages (悪魔祓いの魔導士, Akumaharai no Madōshi).

Trivia

 * This version of the magic was made to better fit the demons in the world of Fairy Tail: Vice