Not a saviour

Dean passes away. With Sam, Cas, and Bobby lost without him, they try all they can to get Dean back or live in his honour. But something's wrong. Even though they burnt his bones after no hope in having a demon bring him back, Cas still senses his presence. Is he imagining it out of loss or is Dean really there? Cas soon finds out the truth about Dean and finally knows what it truly feels like to be human. (This is the first story I've published so bare with me if it's bad. :/)