Katherine Boyle is an original character from Supernatural : The Anime Series. She is a detective and helped the Winchesters on a case. She let them interrogate Zach Evans who claimed to be innocent. She goes along with the brothers to investigate the house for clues. She cuts her finger while unlocking the door. She blushes when Dean ties a cloth to prevent bleeding. She reveals that the victim, Amanda was a friend of hers. She was held captive by the shapeshifter which took her form, to frame Dean for the murders. She was rescued later when the brothers killed the monster.