Lost a Hannibal fic and now I can't know peace

So, I'm super sorry to come in here with this as it may be the wrong place for it. I certainly feel like an uncultured swine, dropping in here with a question about a fic I 've lost when this sub is otherwise filled with so much wonderful, thoughtful discussion about the show!

However, I read this amazing AU fic a couple of years ago, and I Cannot for the life of me find it or remember the name/author, and I was wondering whether it rings any bells with anyone. Please be aware there is a vague description of fairly canon-typical murder below.

The fic is an amazing, long (iirc) AU with some kind of post-apocalyptic setting. Memory is vague, but I'm fairly sure it wasn't a zombie type setting. Hannibal leads a cannibalistic band of survivors, and for some reason Will ends up being taken by them. There's some Stockholm Syndrome going on, as Hannibal uses a mixture of fear/intimidation and comfort to slowly have Will warm up to him. I remember that he spends a lot of the early days shutting Will in a small, completely dark space and only letting him out once he's desperate, so that he associates Hannibal with providing comfort and light. 

Mason is one of Hannibal's band of survivors, but he ends up (I think) trying to kill Will (possibly kidnapping him from Hannibal's compound and torturing him) so Hannibal exacts revenge by retrieving Will (who at this point in proceedings is fully Team Hannibal and has pretty much gone through his Becoming) and then executing Mason (publicly) by way of 'death of a thousand cuts'. This is where my memory peters out, but if anyone has any ideas, I would be super grateful as it's very well-written and it's the most ass-clenchingly annoying thing to be constantly on the verge of almost-remembering it!