Thinner is a novel
by Stephen King
which is considered by many to be one of his most disturbing
The book's main character is an obese man who accidentally runs over a gypsy girl on his way home with his wife. The girl's father is so angered that he puts a curse on him, which makes him become thinner and thinner.
At first, the weight loss is a great thing. Co-workers and family members keep complimenting on how much better he looks. Unfortunantly, the weight loss doesn't stop, and he starts diving below the 100-pound mark.
He starts a search for the gypsy man, and when found, apologizes and begs him to take the curse off. The old man then transfers a curse to a pie, which must be fed to someone else to transfer the curse. The book's ending is cut off, without the reader knowing who the pie is given to.