Being a story with demons, sinners, murderers, and pulling no punches when showing how depraved people can be, this series is chock full of nightmare fuel.
- The 9th Circle of Hell is definitely disturbing. It's a void empty of anything. No sights, sounds, nothing to touch,. Just pitch black and an overwhelming sense of loneliness. Little wonder Scarlet has no desire to go back there.
- The reveal that Jordan was a serial killer who had killed 10 women, and his accompanying facial expressions. He'd seemed like an ordinary guy. Finding out he enjoyed watching blood drain from women was nothing short of chilling.
- The robber that Scarlet and Chase corner at the end of season 1. Once he turns around, it's revealed blood is dripping from their eyes, nose, and mouth.
- Chase absolutely losing it on said robber after he shoots Scarlet in the head and Chase thinks she's died. We've seen Chase lose his temper before, but never to the extent of almost killing someone with his bare hands.
- Every time Scarlet loses control of her demon. The first time is when she starts to lose all faith in humanity and she brutally kills a purse snatcher by stabbing him with her scythe multiple times. The second, after Brook pushes her too far and she effortlessly rips his body to shreds and murders an entire alleyway of sinners and non sinners alike, and ultimately near fatally stabs Chase.
- The reveal that Satan is doing God's will. He was not charged with any crime whatsoever before Falling (in fact, he Fell seconds after he was born), and nothing Satan has done has convinced God to tear him out of existence. All the misery that Satan and the powerful sinners have perpetuated? It's all according to plan.
- The world's population has plummeted to less than one billion. Let that sink in for a bit.
- In the Ninth Circle of Hell, the only thing you have to do is torture yourself with your mind. Scarlet hallucinates a grotesque pile of organs with her face, then it turns into Chase, and at the last second it turns into Satan so she can lose control and smash Chase's head in. She is reduced to a sobbing wreck begging to be let out.
- In the Ninth Circle of Heaven, whatever happens to the souls there causes them to perma-die. Apparently, since God is absent, any soul that is harvested by an archangel will be forced there for processing, hence the reason they haven't performed a Mercy Kill in centuries.
- (Biological) Immortality has been achieved. Which would normally be great, except the shadow dictators of the world have hoarded this secret resource to themselves, allowing them to destroy the world and ascend to demi-godhood in the process, and Heaven still isn't doing anything.
- God's ultimate plan is to consume Heaven (And maybe Earth and Hell. Maybe.). This will, in theory, answer the Ultimate Question: "Who am I?"
- The horrifying implication is that, in a previous universe, God was a 9th-level sinner equivalent, stuck in sensory isolation for a quintillion years, until the sheer amount of time that passed allowed them to subconsciously reach enlightenment and attain godhood. In short, it's possible that every person who is trapped in the 9th circle - every horrible, near-irredeemable monster - will eventually become a god and start their own Crapsack World just to find out who they were, completely unaware that even their past evil self would not go this far because it's insanely boring and a nihilistically pointless use of godhood.
- Scarlet and Bernadette go all-out in their duel to the death, mutating into hideous Humanoid Abominations.
