Detective Nam Ki-ri mentions that since 1997, no one has been executed by death penalty in South Korea, and reference the cases of serial killers Young Chul-yoo and Kang Ho-sun, who are still on death row awaiting execution. Young Chul-yoo is a serial killer, rapist and alleged cannibal who killed at least 20 people, starting with wealthy senior citizens and later targeting female scorts, between years 2003 and 2004. He was sentenced to death on 2004 and by 2018 he's still awaiting execution. Kang Ho-sun is a serial killer who murdered at least 10 people, including his wife and mother-in-law, between 2006 and 2008. He was sentenced to death on 2008 and just like Young Chul-yoo, he's still awaiting execution.
The last executions in South Korea were on December, 1997. 23 prisoners sentenced to death were hanged, 18 men and 5 women. As of 2018, there are 61 prisoners in death row in South Korea.