A lot of people believe that it's Castiel, who's afraid of thunderstorms. Mostly they say, it's because it reminds him of his brothers and god all the times they fought.
But actually it's Dean.
[A SUPERNATURAL FANFIC] Ever since Nova Books could remember she has been on the run. Always looking over her shoulder for the next angle or demon attack. She places her trust in the Winchester boys. Not know what she is or what her connection is to heaven. All she knows is the she has powers no other person has in the world. With the help of Sam, Dean, Bobby, and the irresistible Castiel....maybe she will find her answer.