User blog comment:B214/Question and Answers 6/@comment-26293136-20161211205426/@comment-29963364-20161211214604

Humans who can use Magic are classified as Magicians, but the specifics of them haven't been elaborated in the story.

My own theory is that all beings have two energies:


 * Life Force (Chi/Ki)


 * All beings, no matter the race, has it.


 * Spiritual/Mystic Energy (Magic)


 * The type of Spiritual/Mystic Energy a being has is dependant on their race (Devils have Demonic Power, Angels & Fallen Angels have Light Power, Youkai have Youjutsu, etc.)

Humans, since they aren't a "supernatural" race, have a "Generic" Spiritual/Mystic Energy. And unlike the supernatural races who can naturally manipulate it (like Devils using their Demonic Power to "create" phenomena that they imagine), Humans have to discover and learn how to manipulate it (they use Formulas, Equations, and Calculations to "construct" phenomena).