This scene represents a Deep One lurking around somewhere near the harbor, as described by H.P. Lovecraft in the tale The Shadow over Innsmouth. Part of the Cthulhu Mythos, with both fish and frog features mixed together, this monster is the final form some of the towns dewllers endure at some point of their lives, specially those closely associated with the opprobrious Marsh family. This hideous shape allows them to finally met their ancient kin deep underneath the waters, in the terrible city of R'lyeh.
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