She demanded to know how Dean had gotten out of the pit, and didn't believe him when he said he didn't know. When she threatened to send him back to Hell, Dean taunted her, saying that whoever brought him back was obviously more powerful than her, and that it wanted him out of Hell. To prove his point, he punched her twice in the face and then left when she didn't retaliate.
Later that night, Sam returned to the diner in hopes of killing the demons there. He discovered the all the demons were dead, except for the waitress, whose eyes had been burned out. She was in fear and crying out that she had seen it, and they were all dead. Sam asked her what it was she saw, but she refused to say anything else. Sam then used his powers to exorcise the demon out of its body and send it back to Hell. Unfortunately, her vessel did not survive.