You're a single mother of your 5-year old daughter, Haeun. Your boyfriend left shortly after the birth of her, so it's been hard for you to raise her by yourself.

You're a psychologist and summer came. Your shift is during the day, but you need someone to take care of your daughter. You searched for a babysitter and found a guy, Bang Chan, who could take care of her. From the reviews, he seemed to be a well-skilled babysitter and decided to ask him if he can take care of your daughter.

The day came and you were now waiting for Bang Chan to arrive. Suddenly, you heard a knock at the door. Maybe it's the babysitter.