Ghost Twins

These two unnamed twin sisters were two people Bobby Singer failed to save during a hunt.

Background
These girls' ghosts were summoned as part of the Rising of the Witnesses (one of the seals holding Lucifer captive that Lilith broke) and sent after Bobby Singer to kill him.

At his home, Bobby is confronted by the spirits of these two young girls, who accuse him of failing to save them from the 'monster' that killed them. They capture him and hold him in a wrecked car in his salvage yard while they torment him. Sam Winchester managed to find and rescue Bobby. Bobby leads Sam and Dean Winchester to a safe room in his house.

Bobby found a spell to put the spirits to rest and they left the safe room to prepare the spell. The boys gathered all the supplies for the spell and Bobby with Dean's help complete the spell and the spirits vanished.