A/N: I don't own Gravity Falls or Beauty and the Beast
Prologue: The Curse
Once upon time, as most stories such as this started out, there once lived a noble family known as House Northwest. The Northwest family was once a wealthy and influential noble house that held a large amount of land and governed over the countryside and the village that resided within their territories. As to be expected, one who is born into such wealth and power would make them spoiled and uncaring for others.
Such was the case of the Northwest's only child. The young girl was selfish, greedy and cared little for those around her, thinking she was above them. The girl would usually be seen insulting the servants for making the smallest of errors. Her parents tried to steer their daughter in a more humble direction, but their efforts proved useless as their child only greedier as the days went on.
One night during a terrible storm, an old beggar arrived on the Northwest's home and asked if he could spend the night in Nobel's house or least until the rains stopped and offered the girl a rose as a token of his gratitude. The child, disgusted by the very notion of letting some filthy commoner into her home, turned him away. The old man once again asked her, telling her not to judge one by their appearances. But again, the girl turned the beggar away.
In a flash of light, the old man suddenly transformed into his true form: a wicked demon who had come to put the girl through a test of her humility—a test she had failed miserably. The girl begged for forgiveness, but it was too late to seek mercy. The demon changed the wicked child into a hideous creature and placed a terrible curse upon the castle and all who lived within its walls.
The demon then gave the now monstrous girl the rose he had offered her, telling her that she must find true love before the last rose petal fell if she was to lift the curse. If she failed, then she would remain a monster for the rest of her unnatural days and that those who lived in the castle would be forever cursed alongside her as well.
The years rolled by and the monster's hope of finding a true love faded away, leaving her feeling only rage and despair in her heart. For who could ever learn to love a beast?