Castiel felt as if his soul was being torn away from him, and instantly knew young Dean Winchester was in trouble. Ever since he realised his charge was a guardian he'd forced a link between them that would let him know Dean was in trouble right the same second. He immediately flew down to earth, not caring about hiding his true form behind the veil he normally used.
His true form would be overwhelming, sometimes even deadly, to a mortal, but since Dean was a guardian he should be able to look at him without anything happening to him.
Dean was in agony, and Castiel could feel the pain as if it were his own. Once he was in Dean's bedroom he quickly found the boy, who was on the bed, clearly in pain, but not making a sound. A demon stood over him, his arms stretched in front of him, trying to rip the soul out of the human's body.
Castiel didn't waste a second and quickly advanced on the demon. The demon almost had Dean's soul, and there was only one thing he could do, "Dean, will you allow me to take your soul?" He knew the boy didn't quite understand what that would entail, but all he needed was a confirmation. The child's nod was confirmation enough. The soul immediately went to its new owner: Castiel.
The angel turned back to the demon, which looked ready to strike him, trying to get the soul back. Castiel released his energy, glowing brightly. Forcing his energy to kill the demon.
The demon's smug look disappeared from his face as he felt his skin start to burn away from him piece by piece.
Castiel wanted to smile, for now it was the demon who was screaming in agony. When he couldn't hear the screams anymore, he called his energy back, and after making sure the demon was indeed dead, he turned back to Dean, who was lying unmoving on the bed. He knelt down and gently caressed the child's face, giving the soul back. Although the soul was still technically his, he wanted Dean to have it back so he could grow up to become the man he was meant to be. By accepting the child's soul he practically owned him in the eyes of Heaven.
"Are you all right?" His true voice floated through the room, making it sound as if it was coming from everywhere.
The boy opened his eyes; his soul was still visible in them, and then nodded, never taking his eyes off the beautiful being in front of him. "Who are you?" He asked, amazed.
"I'm an angel," Castiel replied, slightly impressed by the boy's courage. Good, he will need it in life. He thought, sadly.
"O," was all the boy had to say to that.
"Dean, you have to listen carefully," Castiel began. He'd been so focused on saving Dean's soul, he hadn't heard the cry of one of his other charges, and Mary Winchester was in trouble. Knowing he was too late to save Mary, he could still send Dean on his right path. "You have to go to your brother's room and take your brother outside. I'll protect you."
Dean nodded, he didn't understand why he needed to take Sammy outside, but he felt the need to protect Sammy grow stronger and ran out of his room, almost running into his father.
"Take your brother outside as fast as you can. Don't look back. Now Dean, go," his father told him, handing Sammy to him. As he ran all the way downstairs he felt a presence behind to him, he couldn't see anything, but he knew he was safe.
Just as he reached outside he felt the fear well up. The presence was gone, but then his father ran up to him, taking both him and his brother into the safety of his arms. He smiled, it had been his father all along, he realised, as his father took Sammy from him and then hugged his boys close. Yes, his father was the one that had saved him, wasn't he?
The End