Throughout time each culture has had their own way of passing down the morals of society to the newest additions—their children. Each culture had different tales of characters who strayed from the right, to follow the wrong—or those who had stood up for what was right. They have taught countless generations the differences between good and evil, strength and weakness, courage and cowardice. Morality all rolled up into nice little slices of adventure, romance, deceit, and betrayal. But what happens after "happily ever after"? When the page is turned the characters do not sit idly by and wait.
Once upon a time they stepped from the pages into our world, immortal and powerful and free to do as they would - heroes and villains alike - and began to live like mortals. At first they were pure Tales in human form, princesses and evil stepmothers and knights in shining armor thrown into a reality they couldn't fathom, but as time passed the lines started to blur. They learned how the real world works and were forced to adapt—or to attempt to make the world conform to them.
They are not trapped, however. Part and parcel with their power is the ability to change. If Snow White fell in love with a mortal she could abandon her powers and pass them on, becoming fully human and living out a normal life from that point on. The reasons vary, and not everyone has motivations that are so pure; for some it was a means to an end—giving a villain a greater chance to seize power and hold sway over others—but for most, it simply allowed them to live out the life they'd made for themselves in the mortal world. The Tale lived, then, in another body, and the story could continue. And while some took the responsibility seriously and strove to choose their predecessor well, others were careless and wreaked havoc. Some have chosen not to pass on their magic at all.
For the new Tales, then, life becomes different. They are now immortal, gaining abilities they'd never thought possible, and have both the memories of their own previous life and of the Tale that they, now, have lived. It can be just as painful as when they stepped out of the Tales in their first form, especially if their predecessor did not choose wisely...