Body type as visual shorthand for personality and morality in fiction is just... so bad in so many ways. I was talking about Anne McCaffrey over on Tumblr regarding this kind of thing and how she frequently represented her most immoral, lazy and self indulgent characters as being bigger people, which was really weird given that McCaffrey herself was not thin. She seems to have had unhappy thoughts about her own body, given what she said (again, according to my memory of something I read years ago) about a line in her author bio in an interview. The line was, "My hair is silver, my eyes are green and I freckle. The rest is subject to change without notice." She clarified in this interview, that I half remember, that "the rest" was the "bulk" that she "carried around." I'm 99% sure the words I've put quotes around are exact quotes, but I couldn't swear to it under oath. It's sad to me that she seemingly didn't even think of her own body as being like... entirely her body, so much as some baggage that she, a temporarily embarrassed thin person, had been imposed upon to carry.