It occurs to me that since the system has shown the need for Jin-Woo not only to live but to get stronger, the system's threat of "Kill your enemy, or your heart will stop" is more simply motivational.
There are other ways to defeat an enemy, like knocking them out, but I doubt he'd gain much experience.
There are other ways to defeat an enemy, like knocking them out, but I doubt he'd gain much experience.