Forbidden

Certain humans are descended from dragons who had mated with humans long ago. Their union gave their offspring the name of 'Drake' to identify them. With special abilities related to their specific draconic ancestors, they were once treasured people.
However, more recent beliefs is that Drakes are too primal and 'animalistic' to be considered proper humans anymore, despite other hybrid species having arisen since their presence.
Unless they have a 'caretaker', someone who cares for and trains them to compete in fighting championships, they are considered fugitives and are locked up in a holding facility till they are 'adopted' by a prominent caretaker.
This doesn't happen often.
It is normally up to the Drake who their caretaker are to avoid the concept of 'forced slavery' being overtly put forth, despite the underlying irony.
Lastly, there is one condition that binds Drakes to their caretakers. One that's never broken.
They shall never mate.

Warning: May/may not become a mature story.