This character is a
scylla, a monster in Greek mythology. She is depicted as having 12 feet and 6 heads on long, snaky necks, each head having a triple row of sharklike teeth, while her loins were girdled by the heads of baying dogs. From her lair in a cave she devoured whatever ventured within reach.
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Denied. Ok, so that description is just correct for one single depiction of her. Other ancient greek authors use other, wildly different depictions or don't specify things. The only common ground is that she (oh, yeah, we are talking about one specific individual, not a monster-race) was some sort of beautiful water-nypmh whom got turned into some sort of monster by some sort of jealous god.Aside of being super specific, not quite poplar monster, it's also super vague as the tales about her WILDLY differ. Not exactly tag material.