Because at the end, it leads you to believe so by saying:
"I'd like to say that Wolf and I lived happily ever after, but our lives were almost immediately interrupted by another crisis in the kingdoms. But that's not this story; this story is done. And when you live every day with all your heart then you can be happy ever after, even if it's only a short time.
My name is Virginia... and I live on the edge of the forest. And this is the end of the first book of The 10th Kingdom."
—Virginia Lewis
