There are two major types of people you meet in this trade: Insiders and Outsiders. Insiders are humans from this world, normal or otherwise. Outsiders are everything else. It might surprise you, though, how much we share in common. Outsiders aren't as perfect and immortal as the fairytales reported. Of course, Insiders are a bit smarter and deadlier than Outsiders remember too.
Even among us "normal" humans there are important differences in how you got into this business. For instance, Scions are people from Outsider bloodlines that are still mostly human. Attuned seem to be empowered by some greater purpose or pattern. The Cursed have already had their souls and bodies permanently warped and corrupted but somehow managed to pull some of their humanity back together.
Since Outsiders come in all shapes and sizes, it's easiest to group them by how they're shaped. Fairest look sort of like "people" and include elves, trolls, goblins, and just about any boogyman from fairytales. Any other intelligent beast that crawls, swims, or flies can be categorized as Chimera. Lastly, there are also Ephemera, such as ghosts and spirits, that lack a solid physical form.
ASPECTS & FOUNDATIONS
Many living creatures possess special qualities that make them truly extraordinary. These special qualities are called Aspects and make up a critical part of a person's very essence. The Aspects of Outsiders grant them innate magical powers. Many human Insiders also have Aspects, although we don't usually perceive our special abilities as paranormal. A person's spiritual well-being also consists of a number of core principles or values. These values are called Foundations and they're unique for every individual.
There is a common form of magical ritual known as the Contract. The Contract is a magical pact that allows two entities to temporarily exchange Aspects and Foundations. Foundations mostly consist of sentimental value, but being able to borrow someone else's Aspects can be extremely useful. Insiders like to use Contracts to gain the innate magical powers of Outsiders. Likewise, Outsiders need many of the skills and connections that Insiders sometimes take for granted. People who engage in this practice are called Contractors. Because they can tailor their skills and abilities for any job, Contractors are the most valued agents of secret societies and Pantheons.