Sister Dolores was once a Shadowhunter residing in Idris who always had an affinity for crafting objects. She had a husband and children, all of whom were murdered by demons. To escape the pain of their deaths, she joined the Iron Sisters, putting her crafting skills to use to serve her fellow Nephilim, later stating that nothing had ever given her a greater sense of peace. When she joined the Sisters, she chose the name Dolores to signify "sorrow."
In 2007, the Isabelle Lightwood and Jocelyn Fray came to the Adamant Citadel to ask the Sisters for a weapon that could sever the bond between Sebastian Morgenstern and Jace Herondale, where Sister Dolores and Sister Cleophas joined them for a meeting. Sister Dolores told the two that there was no weapon that they could create that would sever their demonic parabatai bond. However, she also told them that a weapon of either Heaven or Hell would be able to do so.
When Isabelle accused them of being cold and impervious to pain and love, Sister Dolores told her of the fate of her family and why she joined the Sisterhood.
Sister Dolores is tall and thin. Her eyes are orange and bright, her face lineless, her hair gray, and her hands are pale white, with long, thin fingers. She wears the Sisters' standard long white gown and wears her hair in braids.