S Diary (Hangul: 에스 다이어리) is a 2004 South Korean romantic comedy film about a woman who decides to interrogate her past lovers about why their relationships failed - then hatches a plot to take revenge on them.On a dreary day, Jin-hee (Kim Sun-a) gets dumped by her boyfriend (Jang Hyuk) with the final note that he was only interested in making love to her but not in a lasting relationship. This triggers her curiosity about whether her past three lovers were also only after her sexual favors.