The vampire was pinned. She wasn't going anywhere. Sam ran a hand along his face, ignoring the bits of pain that were stabbing at him from that brief tussle downstairs and instead taking a brief moment to determine as to what his next move was going to be. They could walk away easily enough. Just leave the vampire there to burn. It was what he would have done on a normal hunt if he'd have gotten pissed off enough at a target like this one. This was different, however. More needed to be done. Killing her alone just wasn't going to be enough to withdraw enough satisfaction from him.
Sam reached into his jacket and withdrew a silver flask. Twisting the cap open, Sam lifted his eyes to meet Ruby's. "You should probably move back," he suggested, tipping the item up so that she'd be able to see what he had in his hand. Holy water. He and Dean carried it around this way sometimes when they had to. It was convenient and inconspicuous. Just how they liked it.