Could someone remind me of the plot of Yeonwoo's Innocence?

So, a few months ago, I was reading the manhwa, but for some trivial reason, I decided to stop reading it for a few months and stop at chapter 56.

I still remember the main story and the names of the important characters, but a lot of it is still hazy in my memory. So I decided to pick up the manhwa again, but I can't be bothered to start all over again.

Could someone give me a short summary of the plot before chapter 56 and tell me who the important characters are?

Many thanks!