Vampire Squid Vampyroteuthis infernalis, not because it sucks blood but "because they have the ability to ‘cape’ themselves up with their membrane, which is black underside, looking just like a vampire wearing a black cape!"
The vampire squid (Vampyroteuthis infernalis, literally: vampire squid from Hell) is actually more beautiful than hellish, I think. This squid does not live at the same depths as the number one entry on this list, but at 600-900 metres, it still dwells a long way down as far as squid are concerned.
Example of bio-luminescence in Firefly squids. You can see the bottom of each squid that shine through the numerous Photospores like the starry sky. Like the firefly squids, this makes vampire squids to try and disguise themselves from predators. Vampire Squid Facts for Kids!
Inverted Vampire squid. Vampire squid have eight webbed arms, tipped with suckers and lined with fleshy spines (called cirri), and two retractable sensory filaments. When threatened, it inverts so that the cirri point outwards in a menacing fashion