As said, I started this story four times before I finally gave in and read it as a whole. I'm bot thappe and sad I did so, this is one of my favourites from you. Definitely top 3. It has so many layers in it. What intriqued me was the feeling of alternative reality - this does not happen in real life - though the settigs were familar and "normal".
What is the background of the families? That was left unsaid and that was a nice touch. The way they bound the kids together in marriage reminds some religions known, but at the same time there was really funny acceptance towards Deus and Zach's gayness. Only one having troubles of Deus and Zach was Z's mum and I think it wasn't because of Zack was gay, but because she was worried about Zach's obsession that she had witnessed him growing up.
Well, gotta love this story. The feeling of destiny is so powerful in this. The meanings of Darkness and Light was explored so beautifully.
Lugh, you amaze me with time and time again.