Eh? Sure they can, because Cay is totes a mage. Not everyone can be, but all the species he knows of in his world have the potential, at least!

[Humans and beastmen and mermaids and fae... all can be mages!]

Because it's my Unique Magic. Everyone has one, and that one's mine. It's suuuuper tiring the more mes I make, though, so Cay has to be careful with it.