Can somebody please give me a summary of what happened in the webtoon "What the skylark says"? Also, I really want to know what's happening particularly in chapter 21. More specifically, what the yellow young girl is saying and what the blue-haired guy is saying near the end of the chapter. I am really intrigued by the webtoon, and if someone could just give me piece of mind, I would be really grateful! Thank you!

Here is the URL of the original comic: http://cartoon.media.daum.net/webtoon/viewer/5562
Here is the URL of Chapter 21: http://cartoon.media.daum.net/webtoon/viewer/6996