Kyungsoo was a street musician, he did it for fun. Being the singer and guitarist himself, he charmed a lot of people who heard it. People who often watched his performance called him by "the charming guy". On his latest performance, there was a sad-looking guy who stared at him in an unamused way. It was very surprising to Kyungsoo. 

What magic could Kyungsoo bring to charm that guy? And who is this guy might be?