Ellen is David's paternal aunt in Brooklyn. She moves in to help take care of him after his mother dies. She is a domineering moralizing presence in the house, and David does not have fond memories of her. Recalling her behavior at parties, he says:
There she was, dressed, as they say, to kill, with her mouth redder than any blood, dressed in something which was either the wrong color, or too tight, or too young, the cocktail glass in her hand threatening, at any instant, to be reduced to shards, to splinters, and that voice going on and on like a razor blade on glass. When I was a little boy and I watched her in company, she frightened me. (1.1.26)
One night, David's father comes home drunk and Ellen accuses him of setting a poor example for David by drinking and sleeping around. As she says, "A man is not the same thing as a bull" (1.1.48). David overhears the conversation and grows distant from his father. Ironically, he had not thought of his father as setting a poor example until Ellen said so.