Dean rubbed at his skin with the towel and finally just wrapped it around his waist, blinking up at Sam curiously until Sam started on about him smiling and he rolled his eyes, moving to grab his clothes with a shake of his head, bundling it all under his arm. Trust sensitive Sammy to pick up on the fact Dean was actually, genuinely happy. Then again, since Purgatory, he'd realised who he was and what he was good at. Then things finally settled down with Sam and... well, he was happy.
"It's call being in love, Sam," he teased, grinning cockily this time as he backed towards the door. "I'm just so head over heels for you, I can't stop smiling." His tone was joking and playful, but there might have been a hint of truth behind it.
"Come on, jackass, just get your clothes and let's go to sleep already," he complained, shaking his head.