Dean raised his eyebrows incredulously as Sam asked if he could join them. Even if he didn't know Sam as well as Sam must know him, he could tell what this was about. It was an age-old move. Especially typical of a guy who had a savior complex and thought Dean was the devil. It would have made him laugh as he remembered the times that move had failed in the bars he'd visited on road trips between hunts, but for the fact what it possibly implied to Luna. The last thing he wanted her to think was that she needed a chaperone to hang around him. He wasn't going to make a move on her. He just wanted to sit. And chat about the stars.
Dean scooted away from Sam slightly with a touchy expression on his face. "Seriously? Not in my lap, dude," he grumbled and reached for a third can of beer. Popping the top, he reached over with the can and tapped Luna's again. "Cheers, my sunny friend," he said with a charming grin at Luna. Then, to cover the irritated expression surfacing on his face, he took a long pull from the beer, consuming half the can in one drink.
Oh, Sam, he thought. If you would just get the fuck out of my head I could possibly blow off a little steam finally. Sam had been with him in the shower when he'd been with Shannon. It had taken a lot of convincing himself to push that away and then he'd succeeded at nothing anyway. Now this. Annoying as hell. He loved his brother but this was pushing it.
Glancing at Luna with another roguish smile, he asked, "You ready for another one?"