From Protector of the Grey House:
Determined to hear her cry out, he brought the flail down on her back, using every ounce of strength granted to him by his vampire blood. He saw the look in her eye, the absolute pain, knowing she would scream. But she didn’t. She tensed greatly, then went slack, closing her eyes. He brought the flail into his other hand, twisting and gripping with all his strength. His teeth were grinding together, anger flowing out of him in waves.
Vincent brought the flail back for another blow, when a female voice stopped him.
“What are you doing?” The feminine voice was stern and disgusted.