Fifteen years ago in this African kingdom, two serial killers were hard at work. Just one of them was human. — Shaun Raviv Jul 7, 2016 (One of Longform’s top 10 stories of 2015.) I. The Sad Man IN MID-MARCH OF 2001, twenty-six-year-old Samantha Kgasi-Ngobese disappeared. She had planned to travel to Mbabane, the capital of Swaziland, a kingdom of a million people in southern Africa, to apply for a job at the High Court…