Erin is an adult woman with red hair. She wears a light pink lipstick.
In I Don't, her hair is in a curly updo. She is seen wearing her white wedding dress and veil with pink floral trim. She is also seen wearing a gold pendant.
She seems to have been raised to be a trophy wife and her aunt Helen thinks she is spoiled by her grandmother like Rita had been before her. In Aunt Nauseam, Rita said she couldn't work as she was raising a child, even though Erin was twenty-four at the time. However, Nauseam mentions Erin does have a secretarial job: one with a salary (rather than wages) and that could support her husband as well.
The marriage, however, would hit some hard times soon after and, in the later episode The Story of D, it is revealed that Erin is thinking of a divorce, stating she had never loved Brian and the only reason for the marriage was that he had given her herpes and she thought no one else would want her.
She would actually start proceedings for a divorce in the episode Aunt Nauseam, hiring Helen to help her and revealing that Brian had gotten her to sign a prenuptial which would sign half of all assets over to him if there was a divorce.
However, the divorce attempt would end when Grandma Barksdale sends her to a spa in Switzerland for a week to 'calm her nerves'. Brian then flies out to Switzerland to talk her out of it and the two end up having a second honeymoon there.
Erin also showed contempt for Paul Meyerson, her mother's then-boyfriend, and irritation with her mother and her dates.
In the episode, Erin was shown doting on her fiancee. She later on states she had never loved Brian and the only reason for the marriage was that he had given her herpes and she thought no one else would want her. Brian then flies out to Switzerland to talk her out of it and the two end up having a second honeymoon there. (As he was reliant on her salary at the time, it is assumed in fanon that Grandma Barksdale paid to fly him to Switzerland to get the couple back together.)
Erin also showed a friendly attitude towards Daria, who dislikes her.