Dean was dumbfounded. He was kissing Cas! And enjoying it.
Cas was very pleased. With himself, with Dean's kiss, and with how he was feeling. The hunter made him feel safe. Dean made Cas' loneliness go away. The angel smiled around the slow kiss.
(Maybe some human feelings are good...) Mused the angel.
Dean's hand glided behind and around Cas' neck. He gripped the angel's hair and kissed the angel harder.
The oldest Winchester was going through the motions, remembering the multitude of girls he had kissed before.
But this was Cas. This was different.
The hunter couldn't remember the last time he had had actual feelings for someone and not just a desire to get laid.
(Wait, wait, wait. Do I even have feelings for Cas?)
Oddly enough, the hunter couldn't bring himself to focus on the question- or anything for that matter.
Cas kissed Dean harder. The hunter responded with enthusiasm.
(I guess the personal space rule gos out the window.) Cas laughed inwardly.
There they stayed. Kissing on the the discolored carpet of the Blue Owl Motel. Arms and sheets tangled around each other.
When the sun came up, the hunter and the angel reluctantly stopped kissing. The both were content and, when they broke apart, sheepishly grinning at one another.
When Sam woke and asked them why they both seemed so tired, the two just shrugged, and when Sam's back was turned, they glanced at one another, smirking.
This would be their little secret for the time being, they would just have to see where these new found feelings took them.