Mitchell County Animal Rescue in North Carolina saved 4-year-old Perdita on Christmas eve after her previous owner died.
The shelter's manager Brittany Taylor told ABC when she first arrived she was "pretty sweet", but things soon took a dark turn.
Due to her devious nature, the shelter decided honesty was the best policy posting a brutal adoption ad on its Facebook page on Thursday.
"Not for the faint of heart," the ad began.
"We thought she was sick, but it turns out she is just a jerk."
