Dean had stuck around after the meeting just for one person. Buffy. Not since Cassie had a woman driven him to distraction and manage to hold onto his interest like the way Buffy did. Add the fact that the tiny little blonde knew everything or at least good enough-what he and his brother did, his dying for Sam and going to hell-it put her in a position that Cassie had no chance of ever reaching. Since she had left. Twice. Both physically and emotionally. Dean didn't want to even think about what it meant that Buffy was in this "position" or about what it meant that she knew a lot about the fucked up life that was Dean Winchester and she still sought him out. She still wanted to have fun with him. And was around to just be there when he was at his lows.
He certainly did not want to think about what he had told her because of the kryptonite. So instead he felt like an idiot and lurked around.
However, his attention managed to be distracted at the mention of pool. He had left some of his stuff in Sam's room from the two times he had stayed there, from the kid thing and second from Alistair kicking his ass. So he had a swim trunk on hand. Yeah, he had a swim trunk. One never knew where there'd get a hunt in Cancun or Miami.
When he saw what the magic people had done, Dean let out an impressive whistle. He was not a fan of magic. Probably never really would be, even though he liked Rose, Ron, Paige and the others well enough. More than even. However, this? Well, he supposed he could get used to things like this.
Having arrived some time after Dawn and Buffy he didn't notice the both at first. However, as he continued to look around, his eyes caught Buffy's and he gave a crooked smile. Before he noticed her sister. "Is this a Summers only party or can a Winchester join in?" He asked them both, before holding his hand out to Dawn. "I don't think we've met. I'm Dean Winchester, one of the natives around here." One of the highly rare natives with the way the arrivals kept on coming.