I like this story a lot :D. I think you captured an important moment for Mirabelle, the time when she realises that the world is big out there, and it's filled with great exciting things and she can reach them all if she works hard and puts her mind into achieving her dream.
                           
The picture that you drew is also very lovely, her posture that is mesmerised by the floating castle and the environment around her that frames the character and making it feel quite dream like. Good job spider ^_^.