Chive

A Chive is a metaphorical passport of your soul that you recieve when you decide to become either a magician or a human. To get to either the Chy or Vy side of the Aqua Zone, a Chive is needed. Before an individual is turned into a magician or a human, they are transported to the Umber Zone, where the Chive is a recieved for travelling between the sides. You will not have a chive if you're a pure human or magician, as it won't be needed as you cannot travel between the sides. The only way you'll be able to recieve a chive is have half magician blood and half human blood. If a newborn was born with half of each side, the baby's soul will immediately be sent to the Umber Zone where it will recieve it's Chive there.

However, there is no law that says not having a chive is bad or good and that you don't have to be one of each side, as it is your choice of whom you want to be.

Broken Chives
How do you break your metaphorical soul passport? You usually can't purposely break your Chives, but the different ways of being transferred to the Nile Zone are:
 * Physically injuring yourself (Such as scraped knees, arms...etc)
 * Losing a magical/human ability (This can't be helped)
 * Having a certain emotion in a certain state
 * Visiting the other side too much