The episode of "Ghost" that was aired on the 21st of June featured a comedic scene where Kim Woo Hyun (So Ji Sub) teases Yoo Kang Mi (Lee Yeon Hee). In the episode, Yoo Kang Mi was enjoying her first day off in a long while when she is suddenly disturbed by music coming from an unidentified source. 

When Yoo Kang Mi finds out that the music is coming from her computer, she is completely shocked and gets even more scared when she sees the blood red background on the computer screen. The people who died in her investigation had seen the same computer screen before they died.

However, the writing that popped up in her computer screen read, "Why don't you wake up already." Yoo Kang Mi was sure that it had been Kim Woo Hyun's joke on her. She then curses him to herself and becomes frustrated at the unpleasant wake-up 'call.'

When Yoo Kang Mi runs into Kim Woo Hyun, she says, "When did you plant a virus in my computer? You're going to get in so much trouble. I'm a member of the cyber investigation unit." Without hesitating, Kim Woo Hyun just says, "I deleted it just now" which made her even angrier.

It has been hinted at that there will be a love line forming between Lee Yeon Hee and So Ji Sub from the way they argue and tease each other like little kids who are crushing on each other. It is especially clear when Yoo Kang Mi gets extremely jealous after hearing that Kim Woo Hyun kissed Goo Yeon Ju.