Your magic was getting out of hand, you were so scared of hurting someone that you tried to run away, but your parents wouldn't let you. Getting angry you accidentally lashed out, leaving no survivors.
Now wandering the enchanted forest alone you come across The Dark One who takes you in as an apprentice and teaches you to control your magic, as it would come of use to him in the future... he just doesn't know why yet...
I will try to make it so the reader can be either male or female, let me know if I make any mistakes. I also want to state that in this story, Belle does not exist... okay, don't hate, but I mean come on it's a Rumple x reader, that would be kinda hard to do if Belle was there to take him away from you, reader-chan, right?
It is also based kinda sorta off the song 'Accidentally in love' obviously.