Good point.
Would one expect a narcissist to have uncreased trousers?
“Trouser crease’s are a mark of attention to appearance either by the man, his wife or his servant.”
WADR, while I have no problem with the gist of your reply, you made an all-too-common mistake in punctuation; e.g., “trouser crease’s.” instead of trouser creases.
By using an apostrophe you did not create the plural of crease; you created SINGULAR POSSESSIVE of crease. Which automatically triggers in the reader’s mind: Trouser crease’s what? Trouser crease’s sharpness? Or trouser crease’s length? Understand? In most cases, a plural can be created from a SINGULAR simply by adding the letter S. But NEVER by adding an apostrophe WITH the S. That creates NOT A PLURAL, but a SINGULAR POSSESSIVE. No charge for the foregoing info. ;oD