The erotic novel Fifty Shades of Grey has made grey ties a fashion must for men hoping to emulate the sexy entrepreneur who wears them in the book. The title also suggest the complexity of the man... hence 50 shades of grey. Since the human eye can only distinguish 32 shades of grey, the title implies that the main character is inscrutable, unable to be figured out.
50 shades of grey is the title of a book by E. L. James. The novel is purely erotic and has attracted a huge female readership. The title relates to the submissive versus dominant relationship between the two main characters in the story.