Sam couldn't look at her. Not really. It stung him to the core, doing this. Having to actually ask Lorne to interpret as to whether or not Ruby was still twisting that knife into their backs. Before, Sam would have never considered doing it. He would have taken her word on every single thing that she told him, no questions asked. It had taken a long time for Sam to find in him to trust a demon. Longer than most people would have taken, in fact. He kept telling himself that trusting her was a terrible idea. Dean would never approve. It was bad. Yet eventually, with time, Ruby did manage to wriggle her way past his defenses. It got to the point where he never believed he'd have to question her word on anything ever again. Now that they were back - no, below - square one, Sam didn't know how to take it. Being there with Dean, Lorne, and Ruby was uncomfortable. Awkward. Tense.
Dean didn't want to be there. He didn't want to be there. Sam was pretty sure that no one except for Ruby wanted to be there and that was also something that could be interpreted differently; after all, no one knew if she was lying or not. Maybe actually going through with this was not something that she wanted to do. Perhaps Ruby was even terrified. She certainly didn't seem it.
As she sang, Sam kept looking to and from Ruby and Lorne. He wanted to see if there was something there that he could identify. A twitch of emotion from Lorne indicating that this was going horribly. Something. Yet Lorne seemed to be good at his job. He was attentive and interested. Sam didn't know what to make of it, so he shoved his hands into his pockets and took to staring at the floor uncomfortably until the entire song was finished. When Lorne began to speak, Sam perked up a little, his attention slipping away from how ridiculous it was that they were actually going through with this to the green demon standing before them. Anxiety spreading, Sam watched Lorne carefully. She was evil, wasn't she? He was going to have to kill her. Just like he'd told Dean. Ruby was going to have to die.
But then Lorne spoke. And all of that fear slowly began to ebb away. Straightening up just a little, Sam looked at Ruby uncertainly. She was telling the truth? Was that even possible? "Are you sure?" Sam turned his gaze back on Lorne. Even though he had been trying to be fairly neutral about this for Dean's sake, there was a look on his face that Sam couldn't fight off. He was hopeful. Very hopeful.