Work the flesh of her bottom
From Lord Of Utterdom
You pick up a small carving knife and slide it across the tender flesh of her back. It splits into a canyon of red meat, pouring a river of blood. Jerianus screams, thrashing against you. She begs you to release her as you carve another line her back. She thrashes now, blood spouting from her wounds and pouring down her lower back, spattering as her body convulses under the pain.
You run the knife against her flesh again and again, but she divulges nothing of the key. Just as you're finally sure she's told the truth, you look across the waste that was once the lovely pale skin of her freckled back. It now is marred with dozens of deep gashes that she certainly won't survive. You drop the knife and leave her splayed across the table, sobbing and bleeding.