Falling Through Hell

Castiel was to save the Righteous Man. Not him, per se, but he would try. He might be simply a Seraph, but it was his job to protect the Earth, which is what saving Dean could do. He dived with the others with the sole intention of saving him. It was completely a surprise when he began to fall in love with him.

Dean Winchester was in agony. That was what Hell's purpose was anyways. Trying to resist Alistair's continuous offer was getting even more difficult. No one was going to save him. Or so he thought.