
Okay, I was way off when I said that the one Seo In kissed was Youngwoon's bullied friend but I admitted I was wrong but also:
"...But I have my own theory as well, I feel like it was Jaewon's idea, I think he blackmailed Seo In to kiss him because he knows that he is Seo In's weakness and deliberately taunts them both and we all know that despite SI's effort to reject Jaewon, he's still has power over him. I also think it was his way to lure YW to beat him up, but we also saw that he beat up Jaewon's ass in that flashback."
Now I just gotta wait and see if I got the beating up part, damn this is so exciting!!!!