Nancy, the secretary at the sheriff's office that was under siege by Lilith's demons, was a devout Catholic. She responded to Sam's request for a towel after Dean got shot, only to be grabbed by him as he stole her crucifix. Later she helped patch Dean's wound.
Voluntarily celibate, she volunteered herself as the virgin sacrifice in Ruby's suggested plan to perform a spell and destroy the attacking demons. Dean, however, didn't approve and came up with an alternate plan that wouldn't require a sacrifice.
Nancy helped during the alternate plan, and survived the siege, only to be killed by Lilith along with the rest of people in the building shortly after Sam and Dean left.
The ghost of Victor Henriksen tells Dean later on that Lilith had flayed Nancy alive, piece by piece, and that Nancy never stopped screaming.
Her death was later avenged after Sam killed Lilith.