Dean – I would put Dean in Gryffindor. This is because he is brave, he always looks after his family and would put himself in danger if it meant that they would be safe. He is also reckless, he made a deal with a demon to safe Sam even though that gave him a year to live. He has knowledge about the monsters he fights but unlike Sam he relies more on his strength and brawn than on the extensive research and knowledge. He is very loyal to his family.
Sam – I found Sam really hard to sort. I wanted to put him in Ravenclaw because he wanted to go to college and pursue a normal life a career. As well as this he always does a lot of the research and it seems even if he turns to hunting he is still very interesting in learning new things constantly. I also wanted to put him in Gryffindor, he not only let Lucifer inside him as a vessel but managed to overpower him enough to get both of them in the cage and Michael as well. This was very brave and was something a Gryffindor would do.
Castiel – Castiel is a really powerful angel but he has a lot of love. I would put Castiel in Hufflepuff. This is because although he stands up for what is right, he doesn’t really want to fight. He wants to keep his family safe and protect the humans that God created but he doesn’t really want to fight if he can help it. He always tries to do the right thing, even though sometimes it doesn’t always go well. He cares a lot about not only Sam and Dean but all the people he meets and that shows that he also has a lot of feelings which a lot of angels don’t have. He also cares about the safety of his family and wants them all to be safe and is prepared to fight if he has to although he prefers it if things can be sorted out peacefully.