Calvin has been working for system of world maintenance and oversees the side characters, he knows how important they can in the development of the plot, and when an error occurs he dresses as a passerby and observes the errors and reports them back to the system. But for some reason recently the plot seems to be deviating more and more. He saw himself locked in a room by the male lead and listened to his words and wondered how a passerby became male leads partner.