A simple "yes" or "no" will not suffice, nor should we ever go the Al Bundy way, who when his wife Peggy once asked him "Does this dress make me look fat?" responded "No, honey. It’s not the dress that makes you look fat. It’s the FAT that makes you look fat."
My recommendation is to always keep it honest.
So when I was posed the question in the post title by my lover yesterday I told him wit the utmost sincerity and honesty, "No, babe, your ass always looks perfectly bodacious and perky. No trousers can ever ruin the way it looks!"