Cassidy, in the 1930s and 40s, was the life of the party. He was always there with a slap on the back and a "How're yez!" He got under your skin and into your heart so close that you couldn't believe it when he stabbed you in the back.
Gilly was a girl from Iowa who had the misfortune to fall for Cassidy. She gave him a place to stay and money from her paycheck. His requests were always so small and so reasonable. A little extra money here and there, and she was slowly pulled down into Cassidy's world of indolence, drugs and addiction.
Eventually, they ran out of money to buy drugs, and had few options left to them other than a long, painful withdrawal. She suggested that she might be able to do sexual favors to get the hits they needed, and Cassidy ruled that out. Then she suggested that he might do those sexual favors.
He broke her jaw.
After her jaw healed and she worked the addiction out of her system, she returned to Iowa, all of her big-city dreams in shreds.