His best guess? It’s because Dean is the Righteous Man. All of Heaven conspired to construct his conception. Every angel
knew when he was born. Every one of them sought to rescue him from Hell. He would never allow Cas to say it, but Dean was a holy man.
It had been ordained.
So in hindsight, it really shouldn’t have been so surprising
to him. Cas had always been aware of the luminescence of Dean’s soul. It was
pure, bright, like how he imagined God Himself to be. But he had never met God.
He had only met Dean Winchester.
He hadn’t noticed the warmth Dean’s soul radiated until his
grace was diminished. For that reason, he believed its strength escaped most
angels. After all, in raw power, a human soul far outstrips angelic grace. But the
soul is meant to be self-contained, while grace is a mobile entity, able to be
shaped and pulled by the angel’s will.
Dean’s soul seems to defy the rules of its Creation.
He realizes this in the most innocuous way. He’s sitting
beside Dean. In the car, one of the most un-angelic places he knows. Yet it is
a place that glows with Dean’s whole presence, even when he is not there. Sam
knows this well.
Cas is sitting there, Dean beside him, and he realizes that
the ache of his stolen grace, burning slowly away, has lessened. At first he
sighs, thankful for the absence of pain. He relaxes, and can’t remember when he
last felt this at ease.
He notices the feeling again when he is standing beside Dean’s
bed that night. Slowly, scientifically, he comes to realize that Dean’s soul is
reaching him. Healing him.
After all, a Holy soul that radiates as pure an energy as
Dean’s…. That’s as close to angel medicine as anything can be.
He finds himself giving more and more excuses to stay close
to Dean. It’s not that he’s using him though. He obviously enjoys Dean’s
company. And he dares to hope Dean feels the same.
And, with increased contact, they uncover new aspects of
their own selves. Dean admits one day that he enjoys having Cas around. Cas
replies that he does not want to imagine his life without Dean, that Heaven is
no longer where the angels live. It’s wherever Dean is. Dean blushes.
One day, Dean notices that Cas is looking healthier. Cas explains,
somewhat ruefully, that somehow, just being around Dean is actually restoring
him. They both look away when he admits this.
And, well. It progresses. Just being around Dean could
sustain Castiel until the end of their lives. But kissing him gives Cas a
warmth that he’s sure is not just his emotions. The closeness they enjoy, the
sharing of love and secrets between their bodies….
Castiel’s diminished grace will never be a problem again.