This is from a collection of sci-fi/fantasy short stories bought many years ago in a second-hand book shop. A friend borrowed the book, loaned it out, and it has never been seen since. I’d love to know the name of the story and author if possible please.
The book cover was orange.
Brief description of plot: A salesman selling a fatal curse visits a workplace — an office I think — and describes this killer curse to the man in question. The man considers its use and decides it would be perfect to eliminate his office nemesis and asks the salesman if he can purchase the curse, only to be shocked and terrified to be told that, in fact, he is not here in fact to sell the curse on this occasion, rather, he is here to deliver it on behalf of someone else, his office enemy who already purchased it — for him. He has been cursed and will soon be dead in a horrific manner....