Caitlin is a woman who worked at Raul's Girls.
Caitlin is one of a handful of women captured by demons and forced into prostitution so they can trade sex for souls. Caitlin is first shown at the brothel and being a cause of displeasure for the demons, since she refuses to wear the clothes picked out for her.
In response, Raul tells Gerald to punish her, but to not leave any marks. Just then, Rowena bursts into the brothel and kills Raul with a hex bag. Gerald flees by escaping his vessel. Afterwards, Rowena invites Caitlin and Elle to come with her.
Rowena takes the girls to a fancy restaurant. She demonstrates her magical abilities by putting a spell on the waiter who wanted them to leave, but then decides to give them top service. Rowena explains that she is a witch, which excites Caitlin, who asks to be taught magic, much to Rowena's delight. When the waiter dies as a side-effect of the magic, the three women flee the restaurant.
Inside Rowena's hotel suite, she prepares the girls for their first test, and orders them to cast a spell on the hotel manager she believes is at the door. However, it turns out to be demons waiting, who promptly take the three as prisoners. Sam and Dean Winchester arrive and rescue them, before setting their sights on the witch. Rowena casts an Attack Dog Spell on Elle, allowing her and Caitlin to flee.
Outside, Caitlin is horrified by what Rowena did to Elle, since the spell is going to kill her. She then punches Rowena and storms off, and before Rowena can cast a spell on her in retaliation, Dean Winchester stops the witch.