I read the beginning of this a while ago on the kink meme, but I can't believe I never commented. Because I love this. I'm usually not a big fan of submissive!Coward, because that usually implies Blackwood being all untouchable and god-like and not caring one bit about him. I liked that, despite everything, this at least hints at something more mutual between them, at so much trust, and that makes submissive!Coward so much more awesome than when he's nothing but a desperate plaything. This here? Perfection:
"Coward flushes, fights the desire to squirm forward and rut against his master's leg like a dog. The flush is one of humiliation, but only on the surface, a thin brittle shell of shame that glows from beneath with pride."

I also loved this line: "It is a throne. Blackwood makes it so simply by sitting there with his true, grand magic, this power of transformation." It just emphasises what authority and power really are - just like Blackwood looked regal and intimidating while sitting in his cell.

All the Bible references made me smirk with glee. Especially the part about Communion ... well, at least these two will never have any doubt about real presence. ;D