[2] It is based on Lee Choong-ho's webtoon Dr. Jekyll Is Mr. Hyde (Korean: 지킬박사는 하이드씨), which gave a romantic comedy spin on the literary character.

He is also in line to become the next CEO of Wonder Group, the conglomerate his family owns, though his cousin Ryu Seung-yeon (Han Sang-jin), who oversees Wonder Hotel is his rival for the position.

Whenever his heart rate exceeds 150, another personality emerges, and unlike Seo-jin's usual cold, cynical and ruthless self, Robin is kind, gentle and has a savior complex.

Because of this, Seo-jin avoids anything that might cause him to have a strong physical or emotional reaction which could trigger Robin's reappearance, even if that means shutting himself away from the world and eschewing any meaningful relationships.

[8] Author Lee Choong-ho, who in 2011 wrote the webtoon Hyde Jekyll, Me was adapted from, alleged on his Twitter account that the screenwriter of Kill Me, Heal Me plagiarized his work.