"And my break is letting you 'take care' of me? Some break that is," he answered, shaking his head a little. He loved his brother, but he didn't think it was in this way until now. There had always been a deep yearning in him for Sam to be near, but that didn't translate into this sort of thing until he was suddenly being humped by Sam on the floor of Rufus' cabin.
Then Sam came out with that, and Dean was reminded of how related they were. This was ridiculous, and he laughed suddenly and sharply, one hand pressing against the wall as he covered his face with the other. "We've actually lost our minds. It's finally happened." He shook his head, looking up at Sam and laughing more, his actually watering from laughing so much.
Finally, he reached out, pulling Sam down with both hands on his face, and kissing him firmly on the lips. "Like I said earlier -- both feet in or both feet out. I'm all in, if you are, but if not then it's fine. We can just go back to normal. But I might have to kiss ya every now and then," he teased, grinning at him.