A lot of deep sea creatures are coloured red, but since the colour blends in so well with dark water it just ends up looking black or dark blue.
In short, combined with the horn-like crown, submerged home, and pitchfork/trident, Poseidon is just another name for the Devil.
Humans misinterpret Hell as an underground cavern of fire, when in reality, it’s a boiling sea floor stoked by hydrothermal vents and exposed magma.
Dante describes the Ninth circle of hell as being where traitors are crushed in a dark frozen lake, which sounds like deep sea trenches or brine pools
Notice how the only thing demons and mermaids have in common is dragging human souls down?
There’s a reason why sailors used to call mermaids “Sea Demons”.
This post is prying open my third eye with a crowbar
Tridents are just pitchforks of the sea.
Bonus points: The Bible describes Hell as a lake of fire and brimstone, aka, sulfur. Sulfur actually burns a bright blue. So every artistic depiction you’ve ever seen of Hell is wrong.
Actual sulfur infused volcano in Indonesia.