Book Rec - Sci-fi Gothic Horror/Cult/Religion

Hey all,

Last night I finished watching Scavenger's Reign (highly recommend if you haven't seen it) which was amazing, but the final scene left me with an itch to find something with a specific feeling. Since it hasn't been renewed, I was wondering if there are books that could scratch it.

Minor spoilers of the end of the series (Nothing to do with plot...)

!At the end of the series, a small shuttle is picked up in space by what appears to be a huge, ornately gilded ship manned by religeous zealots or cultists. The ship is dark, candles on human skulls with beads are seen. The crew who opens the shuttle are dressed in robes and seem to have bound feet. I want to know their story! What happens on a giant cultist ark?!<

I've found The God Engines by John Scalzi - this might be the right direction. Any other suggestions?

Thanks!