This is an extensive story about a vampire who was both blessed and cursed with vampirism. Of course being a vampire is a bad thing, but you've been blessed to be a vampire with some control and restraint over your feeding.
Unfortunately for you, you've been trapped by an ingenious device and have to await the coming of the sun (which is the radiance inviolate mentioned in the story name).
While you're waiting, you have numerous flashbacks. You see how you originally died, how you came to be a vampire, and some other unholy creatures you've met.
While most of the game was linear, there were a few interesting choices and (I think) multiple endings. I ended up with a somewhat romantic ending.
I liked the writing in general. One effective piece of text I liked early on:
"Camille—his maker—had left him a particular imprint; a drive to consume those already craving relief from suffering.
Acts of mercy that fueled him, yes, but also brought him to face that force of nature which he himself refused and resented.
Death."
Overall, by far the best part in this story for me is the dynamic between characters. It's clear the author is talented and experienced at writing interesting conversations and relationships, and that's something I look forward to in future games from this author.