Rebecca and Zach walked into their favorite café.
"Sam! Dean!," she said, when she recognized their old college friend and his brother. Although, she was slightly confused as she heard that they had died a few years ago.
Zach was more than slightly confused. He couldn't understand his sister's delight. Sam's brother had killed his girlfriend, and then beaten Rebecca to near death.
So, he was scared but not surprised, when they turned guns on them. His last thought before he died was, "How could I have been so wrong about Sam?"
Rebecca's last thought was, "Shapeshifters."