Dassa was an anthropology student at Vault-Tec University studying for her PhD in anthropology. While printing her thesis, the Great War broke out and she rushed to Vault 76. However, her father, a Vault-Tec employee, was only able to get two reservations into the vault. Dassa refused to go, insisting that he and her younger brother go to the vault instead of her.
Returning home to Charleston, Dassa survived on her own before enlisting with the Responders. Throughout her years as a Responder, she specialized in leadership, assisting with the recovery after the Christmas Flood and created the Survivor Stories, a series of holotapes recorded by survivors of the War that wanted to preserve their stories.
Dassa's last check-in was on November 5, 2096. She would die some time after that prior to 2102, when her body can be found on a stretcher in the Flatwoods church.