What exactly does the horrible squatting thing foreshadow in "The Monkey's Paw"?
"The Monkey's Paw" is a creepy short story written by W. W. Jacobs that reminds the reader that sometimes wishes do come true--just not always in the exact way in which you hope them to.
A guest in the White home in Laburnam Villa tells the story about the mysterious monkey's paw and how a spell cast upon it will allow three of its owners to have three wishes granted. The current owner, Sergeant-Major Morris, reveals that he is the second owner and that he and the first owner have already successfully been granted their wishes. When he suddenly throws it upon the fire, Mr. White retrieves it and decides to make the final three wishes himself. White's son Herbert then tells his father that he will probably soon find "something horrible squatting up on top of the wardrobe watching you as you pocket your ill-gotten gains."
The "horrible squatting thing" foreshadows the evil nature of the paw, as the previous owner has already warned, and the belief that such an unholy object can only bring horror and ill fortune to the owner. The squatting thing, possibly the reincarnation of the monkey who unwillingly gave up his paw and has returned to witness his revenge, is meant to be a tangible object of evil or death itself.
You will have to read the rest of the story to find out how the three wishes come true in the most horrible way possible.