Terrifying History on Instagram: "Christa Pike, the youngest woman on America’s death row, committed one of the most sadistic crimes in Tennessee history. In 1995, the 18-year-old lured 19-year-old Colleen Slemmer to an abandoned boiler room with two accomplices, accusing her of flirting with Pike’s boyfriend. What followed was pure horror: torture, a pentagram carved into Colleen’s chest, a brick used to crush her skull, and her throat slit. Pike even kept a piece of Colleen’s bone as a trophy—