There's something about waking up next to someone you love that Castiel relishes. The arousal of consciousness being aware that right next to him is a body; strong arms draped around him – relaxed but secure. The warmth that emanates from the person next to him, the soft contact of skin on skin – the sensation of their heartbeat in time with his own…
There's many things Cas adores about waking up next to the person he loves… But most of all, he loves it because it's Dean.
When Dean wakes up first, he always wraps his arms around Cas and pulls him close; he secures Cas, because he wants him to feel safe. Cas thinks that Dean does this for him – but it's as much for Dean as it is for Castiel – Dean doesn't want to lose Cas, he depends on him; he has become a stable point in Dean's life… and Dean doesn't have many stable points – not ones that last anyway. Dean securing his arms around Cas convinces him that at least, for one more day, they are together and they're stable. In that position, Dean can feel the rising and falling of Cas' chest and it is immensely reassuring; Cas, too, feels Dean's heart beating as he wakes cocooned in Dean's arms.
It's a very domesticated experience, cuddling up with someone in bed; it was something that Dean had thought he would never be able to do – not with the kind of life he lived… He had thought that with his life on the road, anyone who he brought into it would be in danger – and he couldn't assure himself he would always be able to keep them safe… So he had forfeited the desire to have those simple things – cuddling in bed with someone; spending time with them; doing something other than hunting; having some semblance of a relationship. He had forfeited them to keep others safe. But that was before he had met Cas.
It had taken a long time, and the two of them had been through so much, before they finally trusted each other entirely. Even then, the progression of their friendship to relationship had taken several long – tension-filled – months; in which Sam urged the both of them to "open up" about how they felt. Dean wasn't usually into all that 'sharing' crap, but he had done it to end the tension between Cas and himself – and through it, he had gained a partner and a relationship.
Each of them gave something unknown to the other, that they both needed, and it was wonderful…
Cas enjoyed those mornings when the two of them could lie undisturbed by the surrounding world – it was like a bubble formed around them which kept everything else out. In those mornings, there was nothing else in the entirety of creation that surpassed the importance of Dean Winchester.
With the two of them, intertwined and connected, there wasn't a single thing that the forces of heaven, hell and purgatory combined could throw at them that they couldn't face…
A/N: I know this is short and kinda wandering, but I'd love to know what you think of it! :)