Although he had everything a person could want, he had no love in his heart
one winters night, an old woman came to the castle begging Castiel for shelter from the cold. In return for this kindness, she offered him a single, perfect Rose.
Disgusted by her rags, Castiel sneered at the rose and turned the poor woman away.
"do not be fooled by appearances" she warned him "there is beauty to be found in all things"
Then in a flash, the woman's ugliness melted away to reveal a lovely enchantress!
As punishment for his selfishness, the enchantress turned Castiel into a hideous beast, the Castle into a dark fortress, and the servants into household objects.
Before she left, she gave him two gifts: a magic mirror that allowed him to see the outside world, and the rose, witch would only live until his twenty-first birthday.
"if you learn to love another and earn her love in return before the last petal of the rose has fallen" said the enchantress, "the spell will be broken, if not, you will remain a beast forever!"