Dean gasps for breath, jaw spasming until he's sucking air through clenched teeth, head pulled back to a painful degree, but he's almost done. He draws the last of the sigil as the fingers that trap his head begin to heat, throat working around an agonized scream at the pain already searing somewhere deep behind Dean's eyes.

Dean's broken arm trembles as he lifts it, but his hand finds its mark with a wet, desperate slap.