The book contains mythology that surrounds the town of Stain'd-by-the-Sea.
There is a chapter about the Stain'd witches, who had ink instead of blood in their veins.
Chapter Seven discusses the Bombinating Beast, which was a mythological creature that was half-horse and half-shark, though some legends claimed half-alligator and half-bear. Named for the bombinating sound it made while looking for prey, it was said to lurk in the waters just outside Stain'd-by-the-Sea and eat humans.
It was claimed that Lady Mallahan slew the beast hundreds of years before, though the author thought that it was more likely that she found a dead walrus on the beach at the bottom of the lighthouse's cliffs, and the local townspeople gossiped until it became interesting.
Some stories claimed that people could tame the beast by imitating its buzz, and there was a myth about a wizard who held the beast under his power as long as he kept the animal fed.
Stain'd-by-the-Sea used to ring a gong in the town square to warn away the beast on moonless nights, and mothers still told their children and husbands that the Bombinating Beast would eat them if they didn't finish their vegetables. Locals of the town would dress as the beast on Halloween and Purim with masks similar to the ones later used by the Inhumane Society, and supposedly, sailors still saw the beast swimming with its body curled up like an underwater question mark.