She was being really insistent on this. She had been before, too, when he brought it up, but now it seemed so much worse than the last time. Sam was having a hard time resisting that face when it looked so sad and miserable, but backing down from everything that he had planned on just because she wasn't comfortable with it was something that he wasn't quite willing to do. If it would help him get rid of Lilith, the demon that had left him empty and broken months ago, then he was going to do it. No doubt about it.
"It's just one exorcism," he told her, looking into her eyes, despite how difficult that was. "I just have to figure out how to do it the right way and then it'll be over. That's it. And I know that it's wrong and that it could go wrong, but...it can't get worse. It's just one thing." Then, just like he had said to Uriel before, he stared at her straight on and said, "I'm not gonna let it go too far. Don't worry."