cult
noun
- a system of religious veneration and devotion directed towards a particular figure or object.
Death cult
A religious movement that worships death or the dead
The second one seems a little tenuous, though Christian religion is obsessed with the crucifixion and the torturing to death of a purportedly innocent individual as vicarious redemption, not just for the things we do, but just for being born at all, original sin etc.
Not a very healthy idea, and I find the notion of vicarious redemption morally repugnant.