From the age of 14, Kim studied abroad in the U.S. She attended Massanutten Military Academy in Virginia and then later the State University of New York, Albany, where she studied economics.

Kim was popular and had a lot of close friends in the U.S.

After graduating, she moved back home to take a job as a professor in Busan, South Korea. Her U.S. friends stayed in touch over the years through Facebook and the messaging app KakaoTalk.

Kim also regularly posted pictures of her friends, crafts, food, and her puppies to Facebook. A friend told BuzzFeed News: "It seemed like she was happy, eating and living well."