If you want more feedback, I would have her tease him more. Especially before she stuffs the cross up his ass. She could force him to confess his sins, and, depending on where you want to go with the story, the sins of his religion. Another idea would be to have her jack him off before she cuts off his dick -- pleasure to pain in one quick motion. Without wanting to demean any of the work, I thought the quality of the writing improve through the piece. I especially liked some of the phasing in part 4.