Dean holds the shell in the palm of his hand, mesmerized by the faint glow until Kisuke begins to draw. It turns his stomach, not the blood, but the sigils, calling to mind more than one deal Dean's made in his life that's gone wrong.

"How's it get inside me?" he asks, already regretting his own curiosity. He'll find out soon enough, and it will likely be as uncomfortable as Kisuke says and more, but it's a favorable distraction from the blood.