Deans' POV
Something about Castiel seems off tonight. Dean can't quite figure out why, but something's definitely different. Since their return from this last hunt he has been unusually distant and seemingly lost in his own thoughts.
Cas had been captured by the monster they were hunting, only to be rescued by Dean less than an hour later. Unharmed (except for rope burns on his wrists and a needle puncture in his arm) and pissed off at himself for being captured, Cas had fallen into this unusually withdrawn behavior.
Maybe Cas was upset at being caught off guard by the creature. Or perhaps he resented having to be rescued. The man was proud of his ability to take care of himself on a hunt. But both he and Dean knew that even the best hunter sometimes needed a backup. Hell, in the past he's saved Deans ass a few times too.
As much as he wants to help, Dean knows that sometimes it's best to give Cas his space. He's more than willing to be there for him. Whether he needs to talk or maybe just someone to hold him. Dean wants to be anything his angel needs.
He and Cas have been together as a couple for a nearly a year now. It has been a mixture of wonder, happiness, and a little fear that it's all just a dream. He didn't think it possible, but he loves the quirky ex-angel more with each passing day. How can you keep increasing something that already feels beyond measure? Damn if he understands it. But there it is.
When he told Cas he loved him, it was the scariest moment of his life. Nothing on Earth or in Hell scared him more than the idea that he might be wrecking their friendship with that action. In the pause between his question and Castiels' answer Dean waited to see if his world would end or begin anew.
It had been a learning experience for both of them. The hunter had never been good with long term relationships. He tended to keep people at a distance because of his dangerous life and (if he was being totally honest here) fear of rejection. Dean Winchester was not as smungly confident as he tried to project. Whereas Cas didn't even totally understand how to express his feelings. They had figured out together how to be a couple.
The sex had, at first, had been a lot of trial and error. Dean really wasn't very experienced with men. Getting the ocasional blow job from a willing guy in an alley or bathroom was as far as he'd ever gone. And Cas, well he was new to everything. The first time Dean caught him watching gay porn the blue-eyed man had turned an adorable bright red. He said he was "doing research" on how to "optomize their performance in bed". It was touching and hilarious at the same time.
So, if Cas needs to work something out in his head, Dean can give him the space. He will be here if he needs him. He will always be here for Cas.
From out of the kitchen where Castiel has gone to get his usual late night fix of herbal tea (How he can drink that stuff is beyond Dean's understanding.) Dean hears the crash of something shattering as it hits the floor.