As much as he craved the blood, Sam could not deny enjoying the fact that he got to be close with Ruby while doing this. It was a good way to excuse taking comfort in being able to sit next to her. His mouth on her body. Her hands on him. If there was anything in this room that he craved as badly as the blood pumping through her veins, it was Ruby herself. He sat close to her, taking the knife from her hands with a sense of confidence that he once severely lacked in. There was a time where Sam hesitated before cutting her; where he feared that in doing so, he would harm her rather than benefit from it by getting the blood. Now it was different. Sam was more comfortable with slicing her open because he knew that she'd be all right. It didn't make him happy knowing that she felt that pain for the time being, but he usually made it up to her. Not that he could now, but he always had before. Always showed Ruby how grateful he was for giving him what he needed to get by. He would again. He wanted to again. Sam would have aimed for something more intimate, if only he wasn't feeling so hesitant on crossing boundaries. So he took her wrist into his hand, briefly met Ruby's eyes with his own, then looked down and focused on her long enough to drag the blade across that familiar spot on her arm. He knew it so well at this point that he probably didn't even have to look to find it.
Without delay, as soon as the knife had done it's job, Sam dropped it onto the floor and pressed his mouth to her wrist. There was a desperate feel to the way that Sam gripped at her arm, his body pressing in as closely to Ruby as he could get while he sucked the blood down in a way that made it seem like he had been terribly dehydrated. In a way, he had been. A low noise escaped his throat, indicating that Sam was getting exactly what he wanted. Her blood - no, his blood. It was his. All his. It happened every time he drank. His senses dulled out, focusing on nothing but the feel of the blood as it slid down his throat. Once in his system, that was it. Nothing else mattered. Nothing but the blood and the power that came with it.