This unnamed demon took possession of Amelia Novak.
When angel vessel Jimmy Novak returns to his family, this demon along with a handful of others decide to kidnap him so they find out how he works.
Due to the intervention of Sam and Dean Winchester, Jimmy survives a confrontation with the demons possessing Rodger and Rodger's wife. In order to keep his wife Amelia and daughter Claire safe, Jimmy decides to leave them and stick with the Winchesters.
As he leaves, this demon reveals itself to Claire by slapping her in the face and saying today just isn't "her day". She then calls Jimmy through Sam's cell phone to inform him of the situation.
Jimmy rushes to a warehouse where this demon, along with three others have Claire bound to a chair. She taunts Jimmy for not coming alone and reveals Sam and Dean have also been captured. Deciding to be rid everyone, she has a demon disarm Sam of the demon-killing knife before she shoots Jimmy in the gut. Another demon proceeds with attacking Claire, but she awakens and smites the demon, revealing that she is possessed by Castiel.
Dean and Sam fight off the other two demons, with Sam draining one of its blood and using his psychic powers to exorcise this demon from Amelia.