When you turn eighteen. The fate of who you truely belong with is written in neat cursive, blocky lettering, or scribbles. A natural phenomenon of course.
However long it may take, your soul mate, depends on your soul mark.
In a world where your soulmate's handprint will appear over your heart when the youngest is born...
A newborn's mark covers up the left side of their body. A twelve year old's mark is a baby's hand.
Some people aren't happy and don't approve. Some make cruel remarks.