Director Kim Jin Won stated that in the Korean title of the drama 세상 어디에도 없는 차칸남자
the word "nice" was purposely misspelled as 차칸 (Cha-kan). The correct
Korean spelling for "nice" should be 착한 (Chak-han). His explained that
“The lead character describes himself as a nice guy but in reality he is
using another person’s love for his own love and is a bad guy who is
only out for revenge. We [purposely misspelled the title] for sarcastic
reasons.” --Source