How do you explain your differences to another person or brain?
Do you start with your personality?.. your physical features?.. what about your dreams?
You see, in this world, anything is possible. You can be whomever you want to be - so long as the mark agrees.
Everyone is born with the mark on the inside of their left wrist. It's large enough to see from 2 metres away but small enough to not draw the eye. Some say we develop the mark overtime. Some say we're simply born with it. But the elders say it is magically binded to us in the womb... they tend to be right about most things.
But, at this point... no one can really confirm where it comes from.
The mark organises everyone in the Kingdom into the life and job they will work towards. The destiny they're born to fulfil.
Some are born into a life of self sacrifice, kindness and honesty. Others are born into a life of danger, bravery and excessive knowledge.
People have documented the numerous attempts to study the marks of our kind, but based off the centuries of scripture and novels that have been written and later studied, it's clear that they nor we, are any closer to finding an answer.
But I guess humans aren't a race quite properly equiped to comprehend the cryptic messages of an ancient species...