J.K. Rowling and Serena

The offending Twitter user, Rob @diegtristan8 drew a backlash for suggesting that Williams was more famous for her body than, say, her victory at Wimbledon on Saturday.

Rowling, who had declared herself via another tweet a member of Team Serena before the championship, joined a chorus of angry responses by dubbing Rob, an idiot:

@jk_rowling @hansmollman ironic then that main reason for her success is that she is built like a man

— Rob (@diegtristan8) July 11, 2015

.@diegtristan8 "she is built like a man". Yeah, my husband looks just like this in a dress. You're an idiot. pic.twitter.com/BCvT10MYkI

— J.K. Rowling (@jk_rowling) July 11, 2015

*Inspired by http://time.com/3954611/jk-rowling-twitter-serena-williams/