IMO, I think Brian was a little impressed with Justin's bravery. He could tell that Justin was full of shit under the lamppost, he could tell he was scared to death at the loft, Brian says he thought Justin was inexperienced, yet Justin was there, he didn't back down from Brian's challenge. Since, Brian is all about sex at this point, I think Brian wanted to see how that would play out once they were fucking,(would he be as bold and courageous sexually?) I don't know that Brian felt any cosmic pull, at least not that soon, But I do think he was intrigued, enough so that he wanted to see what this tough kid was made of, enough so that he wasn't ready to give that up when they were interrupted. I definitely think he had every intention of taking Justin back to the loft and fucking his brains out when he let him come to the hospital. Now knowing how sentimental Brian can be(under the surface) does his feelings start changing at the hospital? maybe. Maybe he's got all this "I'm a dad, he's somebody's son" thing going thru his system along with all the E. I don't know, I'm usually all caught up in watching them at this point in the episode to analyze anything. :) Hope any of this makes some sense.